Tobacco is the common name of several plants in the Nicotiana genus and the Solanaceae (nightshade) family, and the general term for any product prepared from the cured leaves of the tobacco plant. More than 70 species of tobacco are known, but the chief commercial crop is N. tabacum. The more potent variant N. rustica is also used around the world.
Tobacco contains the highly addictive stimulant alkaloid nicotine as well as harmala alkaloids. Dried tobacco leaves are mainly used for smoking in cigarettes and cigars, as well as pipes and shishas . They can also be consumed as snuff, chewing tobacco, dipping tobacco and snus.
Tobacco use is a cause or risk factor for many diseases; especially those affecting the heart, liver, and lungs, as well as many cancers. In 2008, the World Health Organization named tobacco use as the world's single greatest preventable cause of death.
The English word "tobacco" originates from the Spanish and Portuguese word "tabaco". The precise origin of this word is disputed, but it is generally thought to have derived at least in part, from Taino, the Arawakan language of the Caribbean. In Taino, it was said to mean either a roll of tobacco leaves (according to Bartolomé de las Casas, 1552) or to tabago, a kind of L-shaped pipe used for sniffing tobacco smoke (according to Oviedo; with the leaves themselves being referred to as cohiba).
However, perhaps coincidentally, similar words in Spanish, Portuguese and Italian were used from 1410 for certain medicinal herbs. These probably derived from the Arabic طُبّاق ṭubbāq (also طُباق ṭubāq), a word reportedly dating to the 9th century, referring to various herbs.
Tobacco has long been used in the Americas, with some cultivation sites in Mexico dating back to 1400–1000 BC. Many Native American tribes traditionally grow and use tobacco. Historically, people from the Northeast Woodlands cultures have carried tobacco in pouches as a readily accepted trade item. It was smoked both socially and ceremonially, such as to seal a peace treaty or trade agreement. In some Native cultures, tobacco is seen as a gift from the Creator, with the ceremonial tobacco smoke carrying one's thoughts and prayers to the Creator.
Following the arrival of the Europeans to the Americas, tobacco became increasingly popular as a trade item. Hernández de Boncalo, Spanish chronicler of the Indies, was the first European to bring tobacco seeds to the Old World in 1559 following orders of King Philip II of Spain. These seeds were planted in the outskirts of Toledo, more specifically in an area known as "Los Cigarrales" named after the continuous plagues of cicadas (cigarras in Spanish). Before the development of the lighter Virginia and white burley strains of tobacco, the smoke was too harsh to be inhaled. Small quantities were smoked at a time, using a pipe like the midwakh or kiseru, or newly invented waterpipes such as the bong or the hookah (see thuốc lào for a modern continuance of this practice). Tobacco became so popular that the English colony of Jamestown used it as currency and began exporting it as a cash crop; tobacco is often credited as being the export that saved Virginia from ruin.
The alleged benefits of tobacco also contributed to its success. The astronomer Thomas Harriot, who accompanied Sir Richard Grenville on his 1585 expedition to Roanoke Island, mistakenly explained that the plant "openeth all the pores and passages of the body" so that the natives’ "bodies are notably preserved in health, and know not many grievous diseases, wherewithal we in England are often times afflicted." 
In the late 19th century, cigarettes became popular. James Bonsack invented a machine to automate cigarette production. This increase in production allowed tremendous growth in the tobacco industry until the health revelations of the late 20th century.
Following the scientific revelations of the mid-20th century, tobacco was condemned as a health hazard, and eventually became recognized as a cause for cancer, as well as other respiratory and circulatory diseases. In the United States, this led to the Tobacco Master Settlement Agreement, which settled the many lawsuits by the U.S. states in exchange for a combination of yearly payments to the states and voluntary restrictions on advertising and marketing of tobacco products.
In the 1970s, Brown & Williamson cross-bred a strain of tobacco to produce Y1, a strain containing an unusually high nicotine content, nearly doubling from 3.2-3.5% to 6.5%. In the 1990s, this prompted the Food and Drug Administration to allege that tobacco companies were intentionally manipulating the nicotine content of cigarettes.
In 2003, in response to growth of tobacco use in developing countries, the World Health Organization successfully rallied 168 countries to sign the Framework Convention on Tobacco Control. The convention is designed to push for effective legislation and enforcement in all countries to reduce the harmful effects of tobacco.
The desire of many addicted smokers to quit has led to the development of tobacco cessation products.
Many species of tobacco are in the genus of herbs Nicotiana. It is part of the nightshade family (Solanaceae) indigenous to North and South America, Australia, south west Africa, and the South Pacific.
Most nightshades contain varying amounts of nicotine, a powerful neurotoxin to insects. However, tobaccos tend to contain a much higher concentration of nicotine than the others. Unlike many other Solanaceae species, they do not contain tropane alkaloids, which are often poisonous to humans and other animals.
Despite containing enough nicotine and other compounds such as germacrene and anabasine and other piperidine alkaloids (varying between species) to deter most herbivores, a number of such animals have evolved the ability to feed on Nicotiana species without being harmed. Nonetheless, tobacco is unpalatable to many species due to its other attributes. For example, although the cabbage looper is a generalist pest, tobacco's gummosis and trichomes can harm early larvae survival. As a result, some tobacco plants (chiefly N. glauca) have become established as invasive weeds in some places.
Tobacco is cultivated similarly to other agricultural products. Seeds were at first quickly scattered onto the soil. However, young plants came under increasing attack from flea beetles (Epitrix cucumeris or E. pubescens), which caused destruction of half the tobacco crops in United States in 1876. By 1890, successful experiments were conducted that placed the plant in a frame covered by thin cotton fabric. Today, tobacco seeds are sown in cold frames or hotbeds, as their germination is activated by light. In the United States, tobacco is often fertilized with the mineral apatite, which partially starves the plant of nitrogen, to produce a more desired flavor.
After the plants are about 8 inches (20 cm) tall, they are transplanted into the fields. Farmers used to have to wait for rainy weather to plant. A hole is created in the tilled earth with a tobacco peg, either a curved wooden tool or deer antler. After making two holes to the right and left, the planter would move forward two feet, select plants from his/her bag, and repeat. Various mechanical tobacco planters like Bemis, New Idea Setter, and New Holland Transplanter were invented in the late 19th and 20th centuries to automate the process: making the hole, watering it, guiding the plant in — all in one motion.
Tobacco is cultivated annually, and can be harvested in several ways. In the oldest method, still used today, the entire plant is harvested at once by cutting off the stalk at the ground with a tobacco knife; it is then speared onto sticks, four to six plants a stick, and hung in a curing barn. In the 19th century, bright tobacco began to be harvested by pulling individual leaves off the stalk as they ripened. The leaves ripen from the ground upwards, so a field of tobacco harvested in this manner entails the serial harvest of a number of "primings", beginning with the volado leaves near the ground, working to the seco leaves in the middle of the plant, and finishing with the potent ligero leaves at the top. Before harvesting, the crop must be topped when the pink flowers develop. Topping always refers to the removal of the tobacco flower before the leaves are systematically harvested. As the industrial revolution took hold, the harvesting wagons which were used to transport leaves were equipped with man-powered stringers, an apparatus that used twine to attach leaves to a pole. In modern times, large fields are harvested mechanically, although topping the flower and in some cases the plucking of immature leaves is still done by hand. Most tobacco in the U.S. is grown in North Carolina, Kentucky, and Virginia.
Curing and subsequent aging allow for the slow oxidation and degradation of carotenoids in tobacco leaf. This produces certain compounds in the tobacco leaves and gives a sweet hay, tea, rose oil, or fruity aromatic flavor that contributes to the "smoothness" of the smoke. Starch is converted to sugar, which glycates protein, and is oxidized into advanced glycation endproducts (AGEs), a caramelization process that also adds flavor. Inhalation of these AGEs in tobacco smoke contributes to atherosclerosis and cancer. Levels of AGEs are dependent on the curing method used.
Production of tobacco leaf increased by 40% between 1971, when 4.2 million tons of leaf were produced, and 1997, when 5.9 million tons of leaf were produced. According to the Food and Agriculture organization of the UN, tobacco leaf production was expected to hit 7.1 million tons by 2010. This number is a bit lower than the record-high production of 1992, when 7.5 million tons of leaf were produced. The production growth was almost entirely due to increased productivity by developing nations, where production increased by 128%. During that same time, production in developed countries actually decreased. China's increase in tobacco production was the single biggest factor in the increase in world production. China's share of the world market increased from 17% in 1971 to 47% in 1997. This growth can be partially explained by the existence of a high import tariff on foreign tobacco entering China. While this tariff has been reduced from 64% in 1999 to 10% in 2004, it still has led to local, Chinese cigarettes being preferred over foreign cigarettes because of their lower cost.
Every year, about 6.7 million tons of tobacco are produced throughout the world. The top producers of tobacco are China (39.6%), India (8.3%), Brazil (7.0%) and the United States (4.6%).
Around the peak of global tobacco production, 20 million rural Chinese households were producing tobacco on 2.1 million hectares of land. While it is the major crop for millions of Chinese farmers, growing tobacco is not as profitable as cotton or sugarcane, because the Chinese government sets the market price. While this price is guaranteed, it is lower than the natural market price, because of the lack of market risk. To further control tobacco in their borders, China founded a State Tobacco Monopoly Administration (STMA) in 1982. The STMA controls tobacco production, marketing, imports, and exports, and contributes 12% to the nation's national income. As noted above, despite the income generated for the state by profits from state-owned tobacco companies and the taxes paid by companies and retailers, China's government has acted to reduce tobacco use.
India's Tobacco Board is headquartered in Guntur in the state of Andhra Pradesh. India has 96,865 registered tobacco farmers and many more who are not registered. In 2010, 3,120 tobacco product manufacturing facilities were operating in all of India. Around 0.25% of India's cultivated land is used for tobacco production.
Since 1947, the Indian government has supported growth in the tobacco industry. India has seven tobacco research centers, located in Tamil Nadu, Andhra Pradesh, Punjab, Bihar, Mysore, and West Bengal houses the core research institute.
In Brazil, around 135,000 family farmers cite tobacco production as their main economic activity. Tobacco has never exceeded 0.7% of the country's total cultivated area. In the southern regions of Brazil, Virginia, and Amarelinho, flue-cured tobacco, as well as burley and Galpão Comum air-cured tobacco, are produced. These types of tobacco are used for cigarettes. In the northeast, darker, air- and sun-cured tobacco is grown. These types of tobacco are used for cigars, twists, and dark cigarettes. Brazil's government has made attempts to reduce the production of tobacco but has not had a successful systematic antitobacco farming initiative. Brazil's government, however, provides small loans for family farms, including those that grow tobacco, through the Programa Nacional de Fortalecimento da Agricultura Familiar.
The International Labour Office reported that the most child-laborers work in agriculture, which is one of the most hazardous types of work.[failed verification (See discussion.)] The tobacco industry houses some of these working children. Use of children is widespread on farms in Brazil, China, India, Indonesia, Malawi, and Zimbabwe. While some of these children work with their families on small, family-owned farms, others work on large plantations. In late 2009, reports were released by the London-based human-rights group Plan International, claiming that child labor was common on Malawi (producer of 1.8% of the world's tobacco) tobacco farms. The organization interviewed 44 teens, who worked full-time on farms during the 2007-8 growing season. The child-laborers complained of low pay and long hours, as well as physical and sexual abuse by their supervisors. They also reported suffering from Green tobacco sickness, a form of nicotine poisoning. When wet leaves are handled, nicotine from the leaves gets absorbed in the skin and causes nausea, vomiting, and dizziness. Children were exposed to levels of nicotine equivalent to smoking 50 cigarettes, just through direct contact with tobacco leaves. This level of nicotine in children can permanently alter brain structure and function.[failed verification (See discussion.)]
Major tobacco companies have encouraged global tobacco production. Philip Morris, British American Tobacco, and Japan Tobacco each own or lease tobacco-manufacturing facilities in at least 50 countries and buy crude tobacco leaf from at least 12 more countries. This encouragement, along with government subsidies, has led to a glut in the tobacco market. This surplus has resulted in lower prices, which are devastating to small-scale tobacco farmers. According to the World Bank, between 1985 and 2000, the inflation-adjusted price of tobacco dropped 37%. Tobacco is the most widely smuggled legal product.
Tobacco production requires the use of large amounts of pesticides. Tobacco companies recommend up to 16 separate applications of pesticides just in the period between planting the seeds in greenhouses and transplanting the young plants to the field. Pesticide use has been worsened by the desire to produce larger crops in less time because of the decreasing market value of tobacco. Pesticides often harm tobacco farmers because they are unaware of the health effects and the proper safety protocol for working with pesticides. These pesticides, as well as fertilizers, end up in the soil, waterways, and the food chain. Coupled with child labor, pesticides pose an even greater threat. Early exposure to pesticides may increase a child's lifelong cancer risk, as well as harm his or her nervous and immune systems.
Furthermore, the wood used to cure tobacco in some places leads to deforestation. While some big tobacco producers such as China and the United States have access to petroleum, coal, and natural gas, which can be used as alternatives to wood, most developing countries still rely on wood in the curing process. Brazil alone uses the wood of 60 million trees per year for curing, packaging, and rolling cigarettes.
In 2017 WHO released a study on the environmental effects of tobacco.
Several tobacco plants have been used as model organisms in genetics. Tobacco BY-2 cells, derived from N. tabacum cultivar 'Bright Yellow-2', are among the most important research tools in plant cytology. Tobacco has played a pioneering role in callus culture research and the elucidation of the mechanism by which kinetin works, laying the groundwork for modern agricultural biotechnology. The first genetically modified plant was produced in 1982, using Agrobacterium tumefaciens to create an antibiotic-resistant tobacco plant. This research laid the groundwork for all genetically modified crops.
Because of its importance as a research tool, transgenic tobacco was the first GM crop to be tested in field trials, in the United States and France in 1986; China became the first country in the world to approve commercial planting of a GM crop in 1993, which was tobacco.
Many varieties of transgenic tobacco have been intensively tested in field trials. Agronomic traits such as resistance to pathogens (viruses, particularly to the tobacco mosaic virus (TMV); fungi; bacteria and nematodes); weed management via herbicide tolerance; resistance against insect pests; resistance to drought and cold; and production of useful products such as pharmaceuticals; and use of GM plants for bioremediation, have all been tested in over 400 field trials using tobacco.
Currently, only the US is producing GM tobacco. The Chinese virus-resistant tobacco was withdrawn from the market in China in 1997.:3 From 2002 to 2010, cigarettes made with GM tobacco with reduced nicotine content were available in the US under the market name Quest.
Tobacco is consumed in many forms and through a number of different methods. Some examples are:
Smoking in public was, for a long time, reserved for men, and when done by women was sometimes associated with promiscuity; in Japan, during the Edo period, prostitutes and their clients often approached one another under the guise of offering a smoke. The same was true in 19th-century Europe.
Following the American Civil War, the use of tobacco, primarily in cigars, became associated with masculinity and power. Today, tobacco use is often stigmatized; this has spawned quitting associations and antismoking campaigns. Bhutan is the only country in the world where tobacco sales are illegal. Due to its propensity for causing detumescence and erectile dysfunction, some studies have described tobacco as an anaphrodisiacal substance.
Research on tobacco use is limited mainly to smoking, which has been studied more extensively than any other form of consumption. An estimated 1.1 billion people, and up to one-third of the adult population, use tobacco in some form. Smoking is more prevalent among men (however, the gender gap declines with age), the poor, and in transitional or developing countries. A study published in Morbidity and Mortality Weekly Report found that in 2019 approximately one in four youths (23.0%) in the U.S. had used a tobacco product during the past 30 days. This represented approximately three in 10 high school students (31.2%) and approximately one in eight middle school students (12.5%).
Rates of smoking continue to rise in developing countries, but have leveled off or declined in developed countries. Smoking rates in the United States have dropped by half from 1965 to 2006, falling from 42% to 20.8% in adults. In the developing world, tobacco consumption is rising by 3.4% per year.
Tobacco smoking endangers health due to the inhalation of poisonous chemicals in tobacco smoke, such as carbon monoxide, cyanide, and carcinogens, which have been proven to cause heart and lung diseases and cancer. Thousands of different substances in cigarette smoke, including polycyclic aromatic hydrocarbons (such as benzopyrene), formaldehyde, cadmium, nickel, arsenic, tobacco-specific nitrosamines, and phenols contribute to the harmful effects of smoking.
According to the World Health Organization (WHO), tobacco is the single greatest cause of preventable death globally. The WHO estimates that tobacco caused 5.4 million deaths in 2004 and 100 million deaths over the course of the 20th century. Similarly, the United States Centers for Disease Control and Prevention describe tobacco use as "the single most important preventable risk to human health in developed countries and an important cause of premature death worldwide." Due to these health consequences, it is estimated that a 10 hectare field of tobacco used for cigarettes causes 30 deaths per year – 10 from lung cancer and 20 from cigarette-induced diseases like cardiac arrest, gangrene, bladder cancer, mouth cancer, etc.
The harms caused by inhalation of tobacco smoke include diseases of the heart and lungs, with smoking being a major risk factor for heart attacks, strokes, chronic obstructive pulmonary disease (emphysema), and cancer (particularly cancers of the lungs, larynx, mouth, and pancreas). Cancer is caused by inhaling carcinogenic substances in tobacco smoke.
Inhaling secondhand tobacco smoke (which has been exhaled by a smoker) can cause lung cancer in nonsmoking adults. In the United States, about 3,000 adults die each year due to lung cancer from secondhand smoke exposure. Heart disease caused by secondhand smoke kills around 46,000 nonsmokers every year.
The addictive alkaloid nicotine is a stimulant, and popularly known as the most characteristic constituent of tobacco. In drug effect preference questionnaires, a rough indicator of addictive potential, nicotine scores almost as highly as opioids. Users typically develop tolerance and dependence. Nicotine is known to produce conditioned place preference, a sign of psychological enforcement value. In one medical study, tobacco's overall harm to user and self was determined at 3 percent below cocaine, and 13 percent above amphetamines, ranking 6th most harmful of the 20 drugs assessed.
Polonium-210 is a radioactive trace contaminant of tobacco, providing additional explanation for the link between smoking and bronchial cancer. A 1968 study found 0.33-0.36 picocurie polonium-210 (about 0.000,000,000,077 microgram) per gram cigarette tobacco, a tiny fraction of the lethal dose of 1 microgram.
Tobacco has a significant economic impact. The global tobacco market in 2010 was estimated at US$760 billion, excluding China. Statistica estimates that in the U.S. alone, the tobacco industry has a market of US$121 billion, despite the fact the CDC reports that US smoking rates are declining steadily. In the US, the decline in the number of smokers, the end of the Tobacco Transition Payment Program in 2014, and competition from growers in other countries, made tobacco farming economics more challenging.
Of the 1.22 billion smokers worldwide, 1 billion of them live in developing or transitional economies, and much of the disease burden and premature mortality attributable to tobacco use disproportionately affect the poor. While smoking prevalence has declined in many developed countries, it remains high in others, and is increasing among women and in developing countries. Between one-fifth and two-thirds of men in most populations smoke. Women's smoking rates vary more widely but rarely equal male rates.
In Indonesia, the lowest income group spends 15% of its total expenditures on tobacco. In Egypt, more than 10% of low-income household expenditure is on tobacco. The poorest 20% of households in Mexico spend 11% of their income on tobacco.
The tobacco industry advertises its products through a variety of media, including sponsorship, particularly of sporting events. Because of the health risks of these products, this is now one of the most highly regulated forms of marketing. Some or all forms of tobacco advertising are banned in many countries.