smoking

smoking Tobacco is believed to have been grown in the Americas for many thousands of years, and native Americans are thought to have discovered ways of using the plant, including smoking the leaves, a thousand years before Christ. A pottery vessel, found in Guatemala, dated earlier than the eleventh century, depicts a Mayan smoking a roll of tobacco leaves tied with string. Landing at San Salvador in 1492, Columbus was presented with dried fragrant leaves, but threw them away, not realizing the value placed on them by the natives. Rodrigo de Jerez was probably the first European smoker, learning of the practice from Cubans in the 1490s and taking the habit back to Spain. He was imprisoned by the Holy Inquisitors for seven years, but the practice was common by the time he was released. By the middle of the sixteenth century, smoking of tobacco was known in Mexico, Santa Domingo, Cuba, Brazil, Canada (in Montreal), France, Holland, Portugal, Spain, Germany, and Britain. It spread eastwards to Turkey and Poland by the 1580s, and in 1586 the first cautionary remarks about its use were made in Germany, where it was described as the ‘violent herb’. The smoking habit was spread largely by sailors, who both experienced it on their journeys and brought back supplies for continuing use at home. Certainly the naval explorers Sir John Hawkins and Sir Francis Drake, or at least their crews, brought back supplies and made use of the leaves. It was Sir Francis Drake who introduced tobacco to Sir Walter Raleigh in 1585, and, as the story goes, a servant finding Raleigh smoking thought he was on fire and drenched him with beer. Tobacco was smoked in various ways — rolled into a cigar, as cigarettes made with reed stems, and in pipes. Raleigh, while not the originator of smoking in England, did much to improve the method of curing the leaf, and popularized it amongst the courtiers of his day. The rich would smoke the leaf in silver pipes, while in the taverns clay pipes filled with smouldering tobacco would be passed from hand to hand. The poor man made do with a walnut shell and a straw stem. The price of tobacco was high, the purchaser getting enough leaf to balance the silver coins placed on the other pan of the scales. Numerous claims were made for the benefits of tobacco, such as prevention of toothache, falling fingernails, worms, hallitosis, lockjaw, and cancer. In 1566, Catherine de Medici, Queen of France, received snuff (powdered tobacco) to treat her migraine, and later decreed it Herba Regina.

The impact of tobacco, particularly in Europe, was considerable, and often contradictory. For example, importation of tobacco from the colonies prompted governments to impose a heavy duty, which in turn encouraged smuggling, bootlegging, and attempts to grow tobacco at home. In 1604, James I published a ‘counterblaste’ against tobacco, concluding that smoking was
‘a custom lothsome to the eye, hateful to the nose, harmefull to the braine, daungerous to the lungs, and in the blacke stinking fume thereof, nearest resembling the horrible Stigian smoke of the pit that is bottomelesse’.

In the colonies it was realized that the Spanish leaf (Nicotiana tabacum) was superior to the indifferent leaf found in the colonies (Nicotiana rustic), and English colonials were very influential in setting up the tobacco growing industry in Virginia and Maryland, to the obvious advantage to trade. Indeed, an article in the Washington Post in 1997, by Susan de Ford, was entitled ‘Tobacco: the noxious weed that built a nation’ — referring here, of course, to the US. In the Americas a special tax levied in 1693 helped establish the college of William and Mary at Williamsburg, and in the nineteenth century Duke University in North Carolina was founded on tobacco. Spenser's Fairy Queen, published in 1590, contains the earliest poetical allusion to tobacco. Six years later Ben Jonson's Every Man is his humor has a scene in which an argument about tobacco is played out. By 1614 there were 7000 tobacconists' shops in London alone. Cigarettes became the most popular form of tobacco, use by the 1880s, made by huge corporations, particularly in the US, supplying the worlds' smoking needs: pipes were in decline. The taking of snuff and the use of chewing tobacco are now almost extinct, although dedicated pipe smokers and cigar devotees are still to be found.

Over the years increasing statistical evidence related smoking to cardiovascular and lung disease, especially bronchitis, emphysema, and cancer. It is undoubtedly true that the pleasures of smoking are derived from the actions of nicotine on the central nervous system. Nicotine is rapidly absorbed from the mucosal membrane of the mouth and from the lungs, and readily penetrates the nervous system. It also has peripheral actions, tending to increase blood pressure and heart rate. The Surgeon-General's Report in the US in 1964 was the real start of the campaign to prevent or abolish smoking. Vested interests in the tobacco companies promoted ideas to reduce the harmful effects by the introduction of filters and creation of low tar cigarettes. It is the carcinogenic compounds in the tar which are the serious hazard to health, and some, but not all, of these compounds are removed by the filters. People changing to cigarettes with low nicotine content tend to smoke more and draw more deeply. Artificial smoking materials have been developed, consisting of pure cellulose-based material impregnated with nicotine. However, combustion of all plant material, and of pure cellulose, seems to produce some carcinogenic agents. The ultimate in the safe cigarette consists of a hollow tube which is not ignited but releases nicotine as the ‘smoker’ draws air through. Nicotine chewing gum and nicotine patches, which release the alkaloid when applied to the skin, have also been produced as substitutes, largely for those who are breaking the habit.

The taking of nicotine is habit forming, indeed it can be described as addictive. The balance of psychological to physical dependence is generally more towards the former, as physical withdrawal symptoms are less severe than with drugs such as heroin. However, individual tobacco addicts vary enormously in their level of dependence. Some of the pleasures of smoking are due to ritual — particularly so in pipe smokers, who carry a variety of equipment for preparing for a satisfying smoke. Many smokers never do so in the dark, for the curl of the smoke from the pipe or cigarette end is part of the ritualistic satisfaction. Many psychological tests have shown that mental activity and performance is enhanced by smoking, particularly when fatigued — but the young often take up smoking to imitate their peers or idols. Serious programmes to stop people smoking or to prevent the young from starting are now being offered, particularly in the Western world, and the number of public places in which smoking is acceptable has greatly reduced.

To understand why smoking is still so common, despite all that is known about its effects, it is necessary to appeal to experiments made in model systems. In the brain a tract of nerve fibres run from the ventral tegmental area (VTA) of the mesolimbic dopamine system to the nucleus accumbens (NA). When this tract of nerve fibres is activated, dopamine is released in the NA. Application of nicotine to the VTA also causes dopamine release in the NA. Experimental animals which have been trained to self-administer nicotine by lever pressing fail to do so if the mesolimbic pathway from the VTA to the NA is cut. Thus, in this experimental paradigm, release of dopamine in the NA seems to be part of a reward response which reinforces administration. More importantly, other addictive drugs, such as amphetamine, cocaine, or morphine, also cause dopamine release in the NA. Most drugs when administered repeatedly result in desensitization — the cell membrane receptors upon which the drug acts fail to respond or they ‘down regulate’, meaning that the number of receptors decreases, thus limiting the response. This is the basis of tolerance. In the case of nicotine receptors in the brain, the numbers increase with continued and repeated administration of the drug, though not uniformly in all areas of the brain. How this increased number of receptors is related to tolerance is unknown. Tolerance to nicotine does exist, for obviously smokers are used to low levels of nicotine for much of their waking hours and have increased numbers of nicotinic receptors. Yet the non-smoker who for one reason or another takes a cigarette or cigar often shows profound effects not only in the psyche but in the periphery as well, often vomiting and feeling very unwell. Stories of fathers making their children smoke a cigar if caught trying to smoke have claimed lifelong cures by this ruse. Finally, nicotinic receptors are so called because they can be activated by nicotine, as well as by the natural transmitter acetylcholine. Activation of the dopaminergic mesolimbic system by release of acetylcholine in the VTA is presumably involved with pleasurable feelings, even in non smokers.

Alan W. Cuthbert

See also addiction.