Steam distillation of dried root bark produces an essential oil consisting mostly of safrole that once was extensively used as a fragrance in perfumes and soaps, food and for aromatherapy. The yield of this oil from American sassafras is quite low, and great effort is needed to produce useful amounts of the root bark.^{[citation needed]} Sassafras extract was a primary ingredient in root beer. Commercial "sassafras oil" generally is a byproduct of camphor production in Asia or comes from related trees in Brazil. Safrole is a precursor for the clandestine manufacture of the drug MDMA (ecstasy), as well as the drug MDA (3-4 methylenedioxyamphetamine) and as such, its transport is monitored internationally.