TABACCO. — A solanaceous plant, to which C. Linnaeus gave the name Nicotian tabacum in honor of J. Nicot of Villemein, who was the first to cultivate the plant in the Portuguese royal gardens. Numerous species and varieties exist (according to some authors, as many as 60 species), almost all of American origin. The first transport of seeds from Brazil to France dates to 1556 and was carried out by the monk André Thevet.
The practice of smoking t. began in Europe, first in Spain (1570), then in England (1586), having been adopted in its early years especially in France to combat toothache. In the time of Louis XIII, smoking became a voluptuous habit, but at first it was forbidden to smoke in the streets and in public establishments, so much so that special establishments (tabagies) existed for smokers. While the practice of smoking t. was becoming increasingly widespread among the less affluent classes, among the aristocracy, by contrast, the use of snuff had already prevailed in the 17th century. Charles I of England was the first to exploit the smoking habit economically, establishing the State Monopoly.
T., which entered Europe as a medicinal plant, has now practically lost all therapeutic use; only in Greece, Spain, Portugal, and Romania are its leaves officinal and regularly included in the respective pharmacopoeias. In the botanical field, nicotine’s insecticidal action is exploited, using an infusion of t. to combat aphids.
In view of the presence in t. leaves of a percentage of nicotine (an alkaloid highly toxic to the organism) ranging from 0.6 to 7 or 9%, excessive smoking may produce symptoms of poisoning. Today, however, it is held that these are due only in part to nicotine, while, in addition to predisposing individual factors, the liberation of other substances during the combustion of t. also plays a role (pyridine bases, ammonia, phenolic and pyrrolic compounds, hydrocyanic acid, carbon monoxide, formaldehyde, etc.).
Acute poisoning is now rare, owing to the great ease with which the organism becomes accustomed to nicotine. Indeed, it is enough to consider that this would be lethal at a dose of 5–10 centigrams, that in a cigarette (containing approximately one gram of t.) an average amount of centigrams of nicotine is contained, and that by inhaling the smoke approximately 90% of the alkaloid is absorbed. The mechanism of this habituation is not yet clear and appears comparable to that occurring with regard to arsenic. Acute poisoning, often fatal, was more frequent in the past, when tobacco enemas were used against constipation or leaf poultices for eye diseases.
Chronic poisoning, also called “tobacco addiction,” is more frequent and is thought to be caused largely by a particular individual predisposition. The symptoms are principally: cardiovascular (palpitations, arrhythmias, anginal syndromes, intermittent claudication), gastric (dyspeptic in type or even involving gastric ectasia and ptosis), visual (scotomas, nyctalopia, amaurosis, disturbances of color perception), and nervous (insomnia, migraine, tremors, vertigo, vascular spasms), in addition to symptoms of local irritation of the upper airways and the oral mucosa (some authors associate cancer of the tongue, lip, and lung with the action of smoking). The tobacco industry may also give rise to eczematous skin diseases, which are regarded as occupational diseases; abortion is frequent among women working with t.
Tobacco addiction develops with considerable slowness, and its severity depends not so much on the quantity of t. used as, as has already been said, on individual factors not yet known. Many authors agree that moderate use of t. should not be considered harmful in a healthy adult, whereas it may cause serious disorders when lesions of the heart, blood vessels, or nervous system already exist. Treatment of tobacco addiction is based exclusively on discontinuing the use of t.; if no permanent organic lesions exist, all the functional symptoms slowly disappear through this means alone. Withdrawal symptoms are in no way comparable to those of morphine, but are purely psychic in nature and can easily be overcome with a little willpower.