Tobacco: History, Uses, and Economic Impact

Tobacco

Introduction to Tobacco

Tobacco, a plant of the nightshade family. The term is applied also to the cured and processed leaves of certain varieties of the plant, which are used in the manufacture of cigarettes, cigars, pipe tobacco, chewing tobacco, and snuff. Nicotine, an alkaloid contained in tobacco, is used for medical purposes and as an insecticide. Tobacco is one of the most important commodities in world trade, and is of major importance in the economy of the United States.

China is by far the world's leading tobacco producer, with the United States ranking second. Most of the United States crop is produced in North Carolina and Kentucky. The United States exports about half of its production. It also imports large quantities, especially Turkish, or Oriental, tobacco, from Turkey, Bulgaria, Yugoslavia, and Greece.

The Tobacco Plant

The tobacco plant is often called by its genus name, Nicotiana. There are about 60 species, most of them native to tropical America. Some are used for ornamental purposes. Only two speciesN. rustica and N. tabacumare used in commerce. N. rustica, or wild tobacco, is grown commercially only in a few parts of Europe and Asia.

N. tabacum, often called simply tobacco, is the most important species. It has been adapted to cultivation in subtropical and temperate climates in many parts of the world. The plant is an annual, up to 10 feet (3 m) high. The leaves are large and oval, with rounded or pointed ends. Leaves and stems are covered with hairs, some of which exude a sticky fluid. The most commonly cultivated varieties have leaves that vary in length from 20 to 24 inches (50 to 60 cm) and are about half as wide as they are long. The tube-shaped flowers are greenish-cream to pink or red. The seeds are very small, and one plant usually produces 200,000 or more.

Tobacco leaves are large and covered with hairs, some of which exude a sticky fluid.

About 100 varieties of tobacco have been developed. Varieties generally are identified according to the way they are curedfor example, air-cured and flue-cured tobaccosbut are sometimes manes for their place of origin (such as Oriental) or for their, ultimate purpose (such as cigar wrappers).

Growing and Harvesting

Most tobacco plants are first grown in outdoor cold frames or in hotbeds called seedbeds or plant beds; however, some growers in the United States and Canada start tobacco plants in greenhouses. When the plants are five to six inches (12 to 15 cm) tall, they are transplanted to the fields. As the transplanted plant grows, the flower heads are broken off so that the leaves will develop more fully. This process is called topping. For some tobacco varieties, the bottom leaves are also removed at topping time.

Harvesting takes place from 90 to 120 days after transplanting. There are two methods of harvesting tobaccopriming and stalk-cutting. In priming, leaves are gathered periodically as they ripen and are carried to a building called a curing barn. In stalk-cutting, the entire plant is cut when mature. The harvested plants are allowed to wilt in the field before they are carried to the curing barn.

Curing

Curing is a carefully controlled process in which the leaves are gradually dried. There are three major methods of curing tobacco: air-curing, flue-curing, and fire-curing.

Air-curing

Almost all tobaccos that are to be air-cured are harvested by stalk-cutting, and then hung to dry in a well-ventilated curing barn. The tobacco is hung by its stalk and cured for three to six weeks, depending on weather conditions and the kind of tobacco. Artificial heat is used only during cold or excessively humid weather. Oriental tobacco is generally air-cured outdoors on racks.

Air-cured tobaccos used to make cigarettes, pipe blends, and chewing tobacco include Burley, an important type grown principally in Kentucky and Tennessee; Maryland tobacco; and dark-leaf tobaccos from Kentucky, Tennessee, and Virginia. Almost all tobacco used in cigars is air-cured.

Flue-curing

Tobacco that is to be fluecured is harvested by priming. Flue-curing is done in small, tightly constructed curing barns that are artificially heated. The barns were traditionally heated by hot metal pipes, called flues, that carried air from an outside furnace. Today oil and gas burners within the barn are usually used, heating the inside air directly. The flue-curing process takes 3 to 5 days.

Flue-cured tobacco is light- to orange-yellow in color. It is the most widely grown tobacco in the United States and is the most important kind exported. It is used to make cigarettes, pipe tobacco, and chewing tobacco.

Fire-curing

In fire-curing, stalk-cut tobacco is allowed to remain in a curing barn from 3 to 5 days without any artificial heat; then open wood fires are burned in the curing barn for 3 to 40 days. The main purpose of the fire is to give the tobacco a smoky taste and aroma by letting smoke come in direct contact with the leaf. Only a very small percentage of the tobacco produced in the United States is cured in this manner. Fire-cured tobacco is used for snuff, strong cigars, and chewing tobacco.

Grading

Tobacco grown in the United States is graded according to standards set by the U.S. Department of Agriculture. Tobaccos are divided into classes, which in turn are broken down into types. Each class is divided into two or more types, and each type is further subdivided into as many as 170 different grades. Worldwide, tobacco growers produce eight major classes of tobacco. These classes are: air-cured, flue-cured, fire-cured, Perique, Oriental, and cigar filler, binder, and wrapper (all three of which are air-cured). Differences in tobacco classes, types, and grades result from variations in culturing and curing methods, varying soil and climatic conditions, and the variety of tobacco grown.

Marketing

In the United States, growers typically deliver their cured tobacco to warehouses. The tobacco is then graded by a federal inspector and sold at auction.

Tobacco growers have various methods for presenting their crop for sale, depending on the type of tobacco. Loose flue-cured leaves are bundled in large burlap sheets. Burley leaves are pressed into bales. Growers prepare other types of tobacco by tying or twisting several leaves into bunches called hands. In Kentucky, growers of dark air-cured tobacco present their crop for sale while it is still in the curing barn.

After purchase, tobacco for cigarettes is redried. Redrying involves two steps. In the first, the tobacco is completely dried by air blown over the leaf. In the second, a uniform amount of moisture is added to the leaves. The redried tobacco is then stored for up to 18 months before use.

Cigar tobaccos, after purchase, are fermented in large bulks (piles) or in wooden cases. During fermentation the tobacco loses much of its nicotine.

Tobacco Products

Cigarettes

Most cigarettes throughout the world are made of a mixture of flue-cured tobaccos and air-cured tobaccos, including Burley, Maryland, and Oriental. Such cigarettes are known as American blended cigarettes. Each type of tobacco is processed separately after it is taken from storage. Initial processing involves ordering and casing. Ordering, also called conditioning, is the process of moistening the tobacco. Casing is the process of spraying, soaking, or dipping the leaves in flavorings such as fruit juices. cocoa, menthol, or other materials. In addition to providing flavor, many flavoring agents have other useful qualities, such as the ability to improve moisture retention. After casing, the tobacco is toasted, to mellow its flavor, and then reordered.

Finally, the manufacturer blends the tobaccos and cuts the leaves into strips. In one continuous operation, cigarette machines roll the shredded tobacco, seal the paper (made from flax straw fiber) around the tobacco, and cut the cigarette to the desired length. Cigarette machines can roll out 25 to 30 cigarettes a second. About 85 per cent of the tobacco consumed in the United States is in the form of cigarettes.

Cigars

All tobacco used in cigars is air-cured and is classified according to its use in the cigar as filler, binder, or wrapper. The filler is used as the core of the cigar. The binder is wrapped around the filler to give shape to the cigar. Reconstituted tobacco sheet (made from powdered tobacco that is wetted and formed into flat sheets) is often used as a less expensive substitute for natural binders. Cigar wrappers, the most difficult and expensive tobaccos to grow, are used for the outside cover of cigars.

Most cigars are produced by machines that can turn out 800 to 900 cigars an hour. Some cigars are still made by hand.

Smoking Tobacco

Smoking tobacco usually refers to pipe tobacco, but it is also used for hand-rolled cigarettes. More robust styles of flue-cured, air-cured, or fire-cured tobacco are blended, and often heavily flavored, to make pipe tobacco.

Chewing Tobacco

Today most chewing tobacco is made from dark air-cured tobacco grown in Pennsylvania and Wisconsin. There are four principal kinds of manufactured chewing tobaccoplug, twist, finecut, and scrap. Chewing tobacco may be sweetened with such substances as honey or licorice. The use of chewing tobacco declined steadily from the 1930's through the 1960's, but then increased, almost tripling between 1972 and 1991.

Snuff

Snuff is cured tobacco that has been fermented for about two months and ground into a fine powder. It may be blended with spices, menthol, or floral scents. In Europe, snuff is held up to the nostrils and inhaled. In the United States, it is generally held between the cheek and the teeth or between the gums and the cheek. Snuff accounts for the smallest percentage of tobacco products.

Tobacco and Health

The effects of tobacco on health have been disputed from the time tobacco was introduced into Europe. Scientific investigations on the relationship of tobacco to lung cancer and other diseases began in about 1900 when an increase in lung cancer was noted by medical authorities. Since then, numerous studies performed on humans and experimental animals have proven that smoking is a health hazard.

Of all the different uses of tobacco, cigarette smoking has been found to be the most hazardous. Although less research has been done oil cigar and pipe smoking, these uses are believed to be less hazardous, largely because pipe and cigar smokers do not usually inhale. The use of chewing tobacco and snuff can increase the risk of developing cancer of the mouth, throat, cheek, or gums.

As a result of the research, many health agencies throughout the world have issued warnings to the public that smoking is dangerous to health. One of the most important warnings was released in January, 1964, in Smoking and Health; Report of the Advisory Committee to the Surgeon General of the Public Health Service. The report states that Cigarette smoking is a health hazard of sufficient importance in the United States to warrant appropriate remedial action.

In 1965 an act of Congress required that cigarette manufacturers put the following warning on cigarette packages: Caution: Cigarette Smoking May Be Hazardous To Your Health. Another congressional act, which took effect in 1971, banned television and radio advertising of cigarettes and required a somewhat stronger warning on cigarette packages: Warning: The Surgeon General Has Determined That Cigarette Smoking Is Dangerous to Your Health.

In 1984, an act of Congress required cigarette manufacturers to submit a list of chemical substances added to tobacco and required that cigarette packages carry one of the following warnings: Surgeon General's Warning: Smoking Causes Lung Cancer, Heart Disease, Emphysema And May Complicate Pregnancy; Surgeon General's Warning: Quitting Smoking Now Greatly Reduces Serious Risks To Your Health; Surgeon General's Warning: Smoking By Pregnant Women May Result In Fetal Injury, Premature Birth And Low Birth Weight; and Surgeon General's Warning: Cigarette Smoke Contains Carbon Monoxide.

In the 1980's, research indicated that smoke exhaled by smokers and given off by the burning end of a cigarette, cigar, or pipeknown as environmental tobacco smoke, or ETScan cause health problems in nonsmoking adults and children who are exposed to it. These health problems include lung cancer in adults and increased risk of bronchitis, pneumonia, chronic middle ear disease, and asthma in children. Nonsmokers pressured businesses and government agencies to create smoke-free surroundings. In 1990, the United States and Canadian governments banned smoking on airplanes on all domestic flights lasting six hours or less; in 1994, Canada banned smoking on all international flights of Canadian airlines. In many offices and public buildings in these and other countries, smoking has been banned or restricted. In 1993, the U.S. Environmental Protection Agency classified ETS a Group A carcinogenthat is, a substance known to cause cancer in humans.

Smoking and Disease

Evidence in the Surgeon General's report and in numerous other reports shows that cigarette smokers are much more likely to develop, or to die from, such diseases as lung cancer, chronic bronchitis, coronary artery disease, and emphysema than are nonsmokers. Cigarette smoking has been linked to cancer of the lips, tongue, larynx, pharynx, oral cavity, esophagus, pancreas, and bladder. It has also been linked to leukemia.

The likelihood that these diseases will develop increases with the number of cigarettes smoked daily, the number of years of smoking, and age at initiation of smoking. Persons who stop smoking, no matter how many years they have been smoking, considerably lessen their chances of developing those diseases linked with smoking.

Smoking and Pregnancy

Evidence from studies of pregnant women shows that smoking during pregnancy retards fetal growth and development, increases the risk of premature birth and fetal and infant death, and increases the likelihood of respiratory problems during childhood.

Physiological Effects of Smoking

Cigarette smoke is composed of various gases and minute particles of solid substances. When smoke is drawn into the mouth and throat (and into the lungs during inhalation) various portions of the smoke leave a deposit of yellowish-brown material on exposed tissue surfaces.

More particles and gases are retained if the smoke is inhaled and if the cigarette is smoked to the very end. During inhalation, up to 70 per cent of the particles are retained in the respiratory tract. The specific amount of gases retained, however, is not definitely known. Filters have been added to some cigarettes, but there is no evidence that even the best filters eliminate the harmful ingredients of smoke.

More than 4,000 chemical compounds have been identified in tobacco smoke. At least 43 of these compounds are known to be carcinogenic, and several of these have been linked to the development of other diseases. Of the gases, carbon monoxide, hydrogen cyanide, and nitrogen oxide are the most hazardous to health. Carbon monoxide is the main contributor to arteriosclerosis; hydrogen cyanide causes respiratory complications; nitrogen oxide promotes pulmonary disease and emphysema. Particulate matter also contains harmful chemical compounds. Tar is a general term for the thousands of harmful chemical agents in the particulate matter. It is able to penetrate to the far recesses of the lungs and other organs, thus increasing the chance of lung cancer and heart disease for people who smoke.

The respiratory membranes of smokers have been found to be thickened and abnormal in structure. The smoke also impairs the function of the cilia found along the respiratory tract. (The function of these tiny, hairlike projections is to sweep debris away from the lungs.) In addition, smoke causes a constriction of the air passages. The thickening of membranes and the constriction of air passages both contribute to the fact that smokers cannot breathe as easily as nonsmokers nor inhale as much oxygen.

When smoke is inhaled, it also passes through the larynx and causes changes similar to those that occur in other air passages. These changes often lead to a chronic cough, commonly known as smoker's cough.

Of the many components of cigarette smoke, nicotine has received special attention. Nicotine has some physiological effects on the human body. On the central nervous system, nicotine acts as a stimulant, causing a state of increased alertness. In addition, it has a calming effect by triggering the release of beta-endorphins, substances that dull the senses. Nicotine may cause such effects as an increase in the heartbeat rate, an elevation of blood pressure, and an increase in the demand for oxygen by the heart. Nicotine causes smokers to have a higher rate of metabolism than nonsmokers. When people quit smoking, their metabolic rate decreases and they require a smaller caloric intake to maintain weight; if they do not lower their caloric intake, they gain weight.

Smoking As A Habit

Smoking is a habit difficult to break because it is based on such psychological factors as oral gratification and such physiological ones as the action of nicotine on the central nervous system. Nicotine can reduce fatigue and stress, relax muscles, increase alertness, improve concentration, and suppress the appetite for carbohydrates. Over time, smokers develop a tolerance to nicotine that eventually causes physical dependence. Persons who give up smoking often experience withdrawal symptoms caused by lack of nicotine; these include drowsiness, headaches, fatigue, irritability, and loss of concentration.

Nicotine chewing gum is used as a cigarette substitute to help smokers break the habit. However, it can produce such side effects as nausea, soreness of the mouth, and heartburn. The nicotine patch is another product used to help smokers break the habit. The patch is stuck to the upper arm or torso, and nicotine is slowly released into the blood through the skin, reducing withdrawal symptoms. However, many wearers experience burning and itchiness under the patches. A nicotine nasal spray became available by prescription in 1996. Nicotine replacement products are expensive and potentially addicting. Most physicians agree that the most effective way to stop smoking is through motivation, willpower, and the support of family and friends. For those who cannot break the habit, doctors recommend they reduce the number of cigarettes, smoke less of each cigarette, and not inhale the smoke.

History

The American Indians cultivated tobacco before the arrival of Columbus. They cured the leaves and smoked them in pipes or as cigars, or powdered them for snuff. Some also had a form of cigarette in which the tobacco was put into reeds fitted with mouthpieces. The Indians believed that tobacco cured various diseases. Pipe smoking was often part of religious and social ceremonies.

Spanish settlers in the West Indies began cultivating N. rustica in the 1530's and exporting it to Europe before the end of the 16th century. Jean Nicot, a French diplomat, introduced the use of tobacco to the French court in the 1560's. The tobacco genus was named in his honor. Sir Walter Raleigh was instrumental in popularizing smoking in England during the latter half of the 16th century. By the early 1600's, tobacco had been introduced into Asia, Africa, and Australia.

Commercial cultivation of N. tabacum was begun by John Rolfe in Virginia in 1612, and tobacco rapidly became the most important export of the colonies. N. tabacum quickly replaced N. rustica in commercial production because of its milder flavor and aroma. After the Revolutionary War, the domestic manufacture of tobacco products became important in the United States.

While some people believed that tobacco had medicinal effects, its use was opposed by others on the grounds of health and morals from the time it was introduced into Europe. James I of England and Pope Urban VIII tried to discourage smoking, and in the New England colonies in the 18th century, attempts were made to ban it. During the 19th and the early 20th century, many Protestant churches in the United States vigorously attacked the use of tobacco. Opposition on medical grounds became pronounced beginning in the 1960's. According to the U.S. Centers for Disease Control and Prevention, the percentage of adults who smoke cigarettes declined in the United States from about 42 in 1965 to about 23 in 1997.

In 1996, President Bill Clinton announced a broad-based health initiative intended to reduce smoking by young people. His provisions included a requirement were a requirement that merchants verify with photo identification the age of young purchasers of tobacco products, and restrictions on tobacco marketing that is appealing to children and teenagers.

In the mid-1990's, tobacco companies became the target of lawsuits by individuals and states seeking damages for health problems caused by smoking. Forty states sued tobacco companies to recover Medicaid costs of tobacco-related illnesses. In 1998, the tobacco industry and states reached a historic agreement that required manufacturers to reimburse states $26 billion over a period of 25 years for these medical costs. In addition, tobacco companies were required to participate in anti smoking campaigns.

The genus Nicotiana belongs to the nightshade family, Solanaceae.