Oleum Terebinthinae (U. S. P.)—Oil of Turpentine.

Preparations: Confection of Turpentine - Emulsion of Oil of Turpentine - Turpentine Liniment - Compound Liniment of Turpentine - Ointment of Turpentine - Black Liniment
Related entries: Resina (U. S. P.)—Resin - Pix Liquida (U. S. P.)—Tar - Oleum Terebinthinae Rectificatum (U. S. P.)—Rectified Oil of Turpentine

"A volatile oil distilled from turpentine"—(U. S. P.). (See Terebinthina.)
"Oil of turpentine should be kept in well-stoppered bottles, protected from light"—(U. S. P.).
SYNONYMS: Spirits of turpentine, Essence of turpentine.

Preparation and History.—Oil of turpentine is the volatile constituent of the oleoresinous exudate obtained from coniferous trees and known as turpentine (see Terebinthina). The oil is separated by distillation with water or steam; the residue in the still is known as rosin or colophony (see Resina). By subjecting turpentine to a dry heat, an empyreumatic oil is produced, to which the term resin oil is more properly applied. By distilling the leaves or fruit-cones of various species of the natural order Coniferae with water or steam, the so-called pine-needle oils are obtained which have a somewhat different composition (see Oleum Pini Sylvestris).

In former centuries, the large pine forests extending through central Europe westward to the Atlantic, supplied the oils of commerce. In the eighteenth century, American turpentine made its appearance and was first distilled in North Carolina and Virginia. Up to the present time the American oil ranks first in the world's market, the French oil, which is esteemed for its finer odor, ranking second. The center of the manufacture of oil of turpentine in the United States is slowly marching southward, on account of the gradual depletion of the pine forests where the industry is carried out. The leading place of export not long ago was Charleston, South Carolina; now its position is taken by Savannah, Georgia. (For a full account of the manufacture of the oil, on the so-called "turpentine farms," see Dr. Frederick Hoffmann, in Die Aetherischen Oele, p. 310; also See Bastin & Trimble's "North American Coniferae," in Amer. Jour. Pharm., 1896, p. 242.)

Description.—Official oil of turpentine is "a thin, colorless liquid, having a characteristic odor and taste, both of which become stronger and less pleasant by age and exposure to the air. Specific gravity, 0.855 to 0.870 at 15° C. (59° F.). It boils at 155° to 170° C. (311° to 338° F.). Soluble in three times its volume of alcohol, the solution being neutral or slightly acid to litmus paper; also soluble in an equal volume of glacial acetic acid"—(U. S. P.). It is scarcely soluble in water, but is easily dissolved by chloroform, benzol, ether, etc. Of 90 per cent alcohol, 5 to 12 parts are required for complete solution. Old oil dissolves more easily than fresh oil. It dissolves resins, fixed oils, fats, sulphur, phosphorus, many alkaloids and neutral vegetable principles, and is also a solvent for caoutchouc. Unless purified, oil of turpentine has a slightly acid reaction, owing to the presence of acetic and formic acids. "Bromine or powdered iodine acts violently upon it. When brought in contact with a mixture of nitric and sulphuric acids, it takes fire"—(U. S. P.). It also takes fire when brought into contact with chlorine gas. The oil is inflammable, burning with a fierce, red flame and much black smoke. The various oils of turpentine are optically active; the French oil is markedly laevo-rotatory (-20° to -40°) while the American oil is, as a rule, dextro-rotatory (to + 10°), and in rare cases slightly laevo-rotatory (to -2° 5') (Gildemeister and Hoffmann, loc. cit., p. 320). Oil of turpentine is quite volatile at ordinary temperatures. When exposed to the atmosphere, especially in the presence of moisture, it becomes "ozonized," by absorption of oxygen; it thickens, resinifies, and acquires an acid reaction. In this condition it is a strongly oxidizing agent, due to its containing oxygen in some active form, which is not, however, that of ozone; this has been pointed out by Kingzett (1874) and others. Hydrogen peroxide is one of the active products formed. C. Engler and J. Weissberg have more recently shown (Berichte d. Deutsch. Chem. Ges., 1898, p. 3046) that absolutely dry oil of turpentine absorbs a maximum volume of active oxygen at 100° C. (212° F.), no ozone, nor hydrogen peroxide being formed. The oil thus charged with oxygen retains its active properties for years if it is kept in a dark place. Above this temperature oxidation of the oil takes place. Among the products of oxidation of "ozonized" oil are formic and acetic acids, and camphoric acid (C10H16O4), and small quantities of an aldehyde (C10H16O3) (Schiff, Chem. Zeitung, 1896, p. 361), to which the penetrating odor of old, rancid oil is probably due. (For further details on this subject, see Gildemeister and Hoffmann, Die Aetherischen Oele, p. 300.)

Tests.—Oil of turpentine may be adulterated with, petroleum, paraffin oils, or resin. For their detection, the U. S. P. directs that "if a little of the oil be evaporated in a small capsule on a water-bath, it should leave not more than a very slight residue (absence of petroleum, paraffin oils, or resin)"—(U. S. P.). The lighter petroleum oils reduce the specific gravity of oil of turpentine. The heavier paraffin oils may be recognized by not being volatile with steam, and may be identified in the residue by their indifference toward strong sulphuric or nitric acid. A quantitative separation of mineral oils from oil of turpentine, may be effected (Burton, 1890; Allen, 1890) by means of fuming nitric acid which destroys the latter oil only.

Chemical Composition.—Oil of turpentine consists chiefly of hydrocarbons (terpenes), of the formula C10H16 (Houton-Labillardière, 1817). Among these, pinene, boiling point 155° to 156° C. (311° to 312.8° F.), is the most prominent. Camphene, melting point 50° C. (122° F.), boiling point 159° to 160° C. (318.2° to 320° F.), and probably fenchene, boiling point 154° to 156° C. (309.2° to 312.8° F.), are also regular constituents of oil of turpentine, as well as dipentene, boiling point 175° to 176° C. (347° to 348.8° F.), and sesquiterpenes, boiling at higher temperatures. Certain pine-needle oils also contain the hydrocarbons 1-limonene, dipentene, d-sylvestrene, 1-phellandrene and cadinene, and the fragrant ester bornyl (borneol) acetate.

PINENE occurs in two modifications which are chemically identical. Laevo-pinene (Wallach, 1885; Berthelot's terebentene) is the principal constituent of the French oil of turpentine, while dextro-pinene (Berthelot's australene) occurs, as a rule, in the American oil. It is a colorless, mobile liquid, which, to some extent, resinifies and absorbs oxygen when exposed to the air. It is an unsaturated hydrocarbon with one double bond. Accordingly, it combines, when surrounded by ice, with dry hydrochloric or hydrobromic acid gas, the former yielding the solid compound C10H16.HCl, which has the odor of camphor, hence is called artificial camphor. It melts at 125° C. (257° F.), the bromine compound at 90° C. (194° F.). Pinene is best identified by the melting point of its nitroso-chloride (C10H16.NOCl) which lies at 103° C. (217.4° F.). When heated to 250° to 270 °C. (482° to 518° F.), pinene is changed into dipentene, the inactive (racemic) modification of d- and l-limonene, boiling at 176° C. (348.8° F.). Alcoholic sulphuric acid converts pinene into terpinolene and terpinene. Pinene in prolonged contact with diluted mineral acids, is converted into crystallizable terpin hydrate (C10H18[OH]2H2O) (see Terpini Hydras). By the action of sulphuric and glacial acetic acids, pinene forms the alcohol terpineol (C10H18O), which has the odor of hyacinth and is much used in perfumery. By the action of diluted nitric acid, or chromic acid, pinene is oxidized with formation of the lower fatty acids, and terephtalic (C8H6O4) and terebenic (C7H10O4) acids. By distillation with sulphuric acid, pinene is converted into inactive terebene (see Terebenum).

Action, Medical Uses, and Dosage.—The actions of oil of turpentine are complex. It is irritant, stimulant, cathartic, diuretic, vermifuge, and, in relation to chronic mucous discharges, astringent. Given in large doses it occasions fullness of the head, or giddiness, with a feeling similar to that of intoxication, or a state resembling trance; sometimes it gives rise to pain in the stomach, nausea and vomiting, and more frequently it gives rise to violent strangury, bloody urine, and other symptoms of renal or vesical irritation. In small doses long continued, or when absorbed from its external application, or its vapor inhaled, it produces in the urine an odor resembling that of violets, and sometimes produces strangury. Its most constant effect is purgation, and when this occurs, the other effects seldom present themselves. In medicinal doses it warms the stomach, elevates the temperature of the surface, quickens the pulse, and when given at short intervals, in slight doses, it acts upon the kidneys, causing an increased urinary discharge. In the typhoid stage of febrile diseases, especially when intestinal ulceration is diagnosed from the symptoms, the tongue becoming dry and dark-colored, the skin dry and husky, and tympanites is present, with occasionally mental derangement, small doses given at short intervals and continued for some time, will act as a stimulant and remove all these symptoms. It is supposed, in these instances, to normally influence the ulcerated tissues. It is likewise recommended in neuralgia, chronic rheumatism, dropsy, suppression of urine, worms, especially taeniatympanitic distension in typhoid fever, peritonitis, or other diseases—chorea, hysteria, croup, colic, jaundice, and in cases where gravel is habitually carried off by copious discharge of lithic acid and lithate of ammonium. It has a tendency to diminish excessive mucous discharges, and has been employed with advantage in chronic catarrh, chronic bronchitis, fetid bronchitis, and pulmonary gangrene (in lung troubles by inhalation as well as internally), chronic dysentery, chronic diarrhoea, chronic inflammation of the bladder, gleet, chronic gonorrhoea, and leucorrhoea. The dose in ordinary cases is from 6 drops to ½ fluid drachm, and even to 1 drachm, at intervals of an hour or two in acute and every 3 or 4 hours in chronic diseases. In the course of its action it is absorbed, and imparts its odor to the breath and perspiration. In doses varying from 20 minims to 1 fluid drachm, according to the urgency of the symptoms, and repeated every 3 or 4 hours, it is a most efficacious astringent, and may be used in epistaxis, hematemesis, hemoptysis, and other sanguineous discharges. It may be administered in water, flavored with some agreeable aromatic syrup, or in infusion of matico, in hemoptysis; in the decoctions of uva ursi, epigaea, or eupatorium, etc., in hematuria; or in the decoction or infusion of cinchona, in purpura hemorrhagica. Where much arterial blood has been lost, tincture of chloride of iron will form a valuable adjunct. Combined with castor oil, it is an excellent vermifuge. It probably prevents the formation of biliary calculi. Externally it is a rubefacient, and is used as a counter-irritant in the form of liniment in rheumatism, paralysis, neuralgia, inflammation of internal organs, in the neighborhood of indolent tumors, to chilblains, indolent and erysipelatous ulcers, caries, sloughing, especially from pressure in exhausting diseases, gangrene, chronic inflammation of the edge of the eyelids, and, combined with linseed oil, in recent burns or scalds.

Turpentine, locally and internally, has given signal results in diphtheria and sciatica. In the latter affection about 30 drops, 3 times a day, is the proper dose. It forms a good local application in mammitis, pleurisy, pneumonia, bronchitis, laryngitis, and rhus poisoning. It has given relief in puerperal peritonitis. Its vapor kills the itch insect. Where deafness is occasioned by a scanty or abnormal secretion of cerumen, the oil of turpentine rubbed up with some bland oil, may be passed into the ear, on cotton. In amenorrhoea arising from torpor of the uterine vessels, in obstinate constipation, in tympanites, or when the bowels are distended with flatus, and in ascarides, oil of turpentine used as an injection will frequently be found a superior remedy. From 4 to 8 fluid drachms may be rubbed up with half a pint of water and the yolk of a few eggs, or with some mucilage, and injected into the rectum, where it should be retained for some time. When given internally, it may be administered in simple or aromatized syrup, or rubbed up with sugar, or taken in gin, when not contraindicated, etc.; or it may be triturated with the yolk of egg, gradually adding syrup and essence of cinnamon, with a portion of water. One yolk is sufficient for trituration with every 2 fluid drachms of the oil. In tapeworm, it has been combined with gin, and given in doses of 1 or 2 fluid ounces. As an ordinary vermifuge, 3 or 4 parts of castor-oil may be added to 1 part of the oil of turpentine.

Dr. James Warren has used a preparation for a number of years in the treatment of hemorrhages, with uniform success. It acts both by its sedative power, in diminishing the force of the circulation, and by its astringent qualities, in contact with the bleeding vessels. He is satisfied that no known remedy exerts a more specific power and gives more speedy relief, especially in hemoptysis, hematemesis, epistaxis, and menorrhagia. Dr. Warren terms it Styptic Balsam. It is made as follows: Place sulphuric acid, 5 drachms by weight, in a Wedgewood mortar, and slowly add to it oil of turpentine 2 fluid drachms, stirring it constantly with the pestle; then add in the same manner alcohol 2 fluid drachms, and continue stirring until no more fumes arise, when it maybe bottled, and should be stopped with a ground stopper. It should be prepared from the purest materials; and when made should exhibit a dark but clear red color, like dark blood; but if it be a pale, dirty red, it will be unfit for use. The dose is 40 drops, to be used as follows: into a common-sized teacup put a teaspoonful of brown sugar, thoroughly incorporate the 40 drops by rubbing together, and then slowly stir in water until the cup is nearly full, when the mixture should be immediately swallowed. The dose may be repeated every hour, for 3 or 4 hours, and its use should be discontinued as soon as fresh blood ceases to flow. After standing a few days, a pellicle forms upon the surface of the balsam, which should be broken, and the liquid below it used. If in well-stoppered bottles, age does not deteriorate it (N. Y. Jour. Med.). French oil of turpentine and old oil of turpentine are antidotes to poisoning by phosphorus.

Related Oil.—ABIETENE (C7H16). This highly volatile and very inflammable oil was obtained by Prof. W. T. Wenzell (Amer. Jour. Pharm., 1872, p. 97) from the terebinthinous exudate of the Nut pine or Digger pine (Pinus Sabiniana, Douglas. of California. The nut of this species is eaten by the Digger Indians. The crude oil is colorless and boils from 101° to 115° C. (213° to 239° F.); the boiling point of the largest fraction is 101° C. (213° F.). Its specific gravity is 0.694; its odor penetrating, strong, and orange-like. According to T. E. Thorpe (Chem. News, 1879), it is identical with heptane (C7H16), one of the low-boiling petroleum hydrocarbons.

Abietene (heptane) dissolves both bromine and iodine without fulmination, and is soluble, in 95 per cent alcohol (5 parts). According to Prof. Sadtler (Amer. Jour. Pharm., 1879, pp. 176 and 293), an oil of the same composition is furnished by the Californian Pinus ponderosa, of Douglas.

King's American Dispensatory, 1898, was written by Harvey Wickes Felter, M.D., and John Uri Lloyd, Phr. M., Ph. D.