Oleum Tanaceti.—Oil of Tansy.
Related entry: Tanacetum (U. S. P.)—Tansy
The very poisonous, oxygenated volatile oil distilled from Tanacetum vulgare, Linné (Nat. Ord.—Compositae).
Description and Chemical Composition.—Oil of tansy is prepared by distilling the flowering herb with water. It is usually yellow, sometimes of a green color, turning brown on exposure to air and light, a warm, extremely bitter taste, and an odor like that of tansy, but more intense. An oil distilled from English cultivated tansy (Schimmel & Co., Report, Oct., 1895) had a camphoraceous odor resembling rosemary, and upon cooling to 0° C. (32° F.) deposited part of its camphor. It also differed from American and German oils by being laevo-rotatory (-27°), the former exerting a right-handed optical rotation (+30° to +45°). Oil of tansy is soluble in alcohol; the American oil, when pure, forms a clear solution also with 70 per cent alcohol. The specific gravity of oil of tansy (fresh plant) varies from 0.925 to 0.940; dry herb 0.955. The yield of oil ranges from 0.10 to 0.20 per cent for fresh, and 0.20 to 0.30 per cent for dry herb (Schimmel & Co.). The characteristic odor of oil of tansy is due to its chief constituent thujone or tanacetone (Bruylants, 1878; Semmler, 1892). It is a ketone (C10H16O) boiling at 203° C. (397.4° F.), and combines with sodium bisulphite, and forms an oxime with hydroxylamine. The oil also contains preformed (Schimmel & Co.) the laevo-rotatory modification of camphor (C10H16O) with small quantities of borneol; a terpene boiling at 160° C. (320° F.) is likewise present (Bruylants).
Action, Medical Uses, and Dosage.—Oil of tansy possesses the properties of the plant (see Tanacetum), but is seldom employed internally on account of its bitterness. It has been employed to produce abortion, but almost always with fatal results. Dose of the oil from 2 to 5 drops. According to Peyraud (1887), the oil produces in animals a disease similar to hydrophobia, called "rage tanacétique" (Gildemeister and Hoffmann, Die Aetherischen Oele, 1899, p. 890).