The new odor, a commingling of
the vapors of turpentine, rotten eggs and old oysters, comes from dimethyl sulfoxide, better known as DMSO, the controversial and often illegally used drug hailed by a growing legion of amateur and professional athletes who view it as a panacea for many ills ranging from sprained ankles to tendinitis and ripped muscles.
Commercial
vapor rubs are typically petroleum based and add camphor which has been synthetically derived from the oil
of turpentine and menthol, which is typically synthetically made.