Also Known As: Methyl salicylate, Thera-gesicm Wintergreen oil
Methyl salicylate (oil of wintergreen or wintergreen oil) is an organic ester that is naturally produced by many species of plants. Some of the plants which produce it are called wintergreens, hence the common name.
Methyl salicylate is used in high concentrations as a rubefacient in deep heating liniments (such as Bengay) to treat joint and muscular pain. Randomised double blind trial reviews report evidence of its effectiveness that is weak, but stronger for acute pain than chronic pain, and that effectiveness may be due entirely to counter-irritation. However in the body, it metabolizes into salicylates, including salicylic acid, a known NSAID.
It is used in low concentrations as a flavoring agent (no more than 0.04%; it is toxic). It is also used to provide fragrance to various products and as an odor-masking agent for some organophosphate pesticides. If used excessively, it can cause stomach and kidney problems.
Methyl salicylate is among the compounds that attract male orchid bees, who apparently gather the chemical to synthesize pheromones; it is commonly used as bait to attract and collect these bees for study.
Methyl salicylate has the ability to clear plant or animal tissue samples of color, and as such is useful for microscopy and immunohistochemistry when excess pigments obscure structures or block light in the tissue being examined. This clearing generally only takes a few minutes, but the tissue must first be dehydrated in alcohol.
Methyl salicylate, though its source plants are not true mints, is used as a mint in some kinds of chewing gum and candy, as an alternative to the more common peppermint and spearmint oils. It can also be found as a flavoring of root beer. It is also a potentially entertaining source of triboluminescence; when mixed with sugar and dried, it gains the tendency to build up electrical charge when crushed or rubbed. This effect can be observed by crushing wintergreen Life Savers candy in a dark room.
Methyl salicylate can be used as a transfer agent, to produce a manual copy of an image on a surface.
Methyl salicylate is added in small amounts to glacial acetic acid to lower its freezing point for transport in cold countries.