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Cigarette

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Image:Zwei zigaretten.jpg
Unlit filtered cigarettes.

A cigarette is a product consumed via smoking and manufactured out of cured and finely cut tobacco leaves and reconstituted tobacco, combined with other additives,[1] then rolled or stuffed into a paper-wrapped cylinder (generally less than 120 mm in length and 10 mm in diameter). The cigarette is ignited at one end and allowed to smoulder for the purpose of inhalation of its smoke from the other (usually filtered) end, which is inserted in the mouth. They are sometimes smoked with a cigarette holder. The term cigarette, as commonly used, refers to a tobacco cigarette but can apply to similar devices containing other herbs, such as cannabis.

Cigarettes are proven to be highly addictive, as well as a cause of multiple types of cancer, heart disease, respiratory disease, circulatory disease, birth defects (which include mental and physical disability) and emphysema.[2][3]

A cigarette is distinguished from a cigar by its smaller size, use of processed leaf, and white paper wrapping. Cigars are typically composed entirely of whole-leaf tobacco.

Cigarettes contain nicotine, an addictive stimulant which is toxic. They deliver smoke to the lungs immediately and produce a rapid psychoactive effect.[4]

Contents

History

Image:Mayan priest smoking.jpg
A reproduction of a carving from the temple at Palenque, Mexico, depicting a Mayan priest smoking from a smoking tube.

The earliest forms of cigarettes have been attested in Central America around the 9th century in the form of reeds and smoking tubes. The Maya, and later the Aztecs, smoked tobacco and various psychoactive drugs in religious rituals and frequently depicted priests and deities smoking on pottery and temple engravings. The cigarette, and the cigar, were the most common method of smoking in the Caribbean, Mexico and Central and South America until recent times.[5]

Cigarettes were largely unknown in the English-speaking world before the Crimean War, when British soldiers began emulating their Ottoman Turkish comrades, who resorted to rolling their tobacco with newsprint.[6]

The cigarette was named some time in the 18th century: beggars in Seville began to pick from the ground the cigar ends left by the señoritos ("rich, young men"), wrapped the tobacco remains with paper and smoked them. The first attested use in this habit can be seen in three 18th-century paintings by Francisco de Goya: La cometa (The Kite), La merienda en el Manzanares (Picnic by the River Manzanares) and El juego de la pelota a pala (The Ball and Paddle Game).

In the George Bizet opera Carmen, which was set in Spain in the 1830s, the title character Carmen was at first a worker in a cigarette factory.

The use of tobacco in cigarette form became increasingly popular during and after the Crimean War. This was helped by the development of tobaccos that are suitable for cigarette use. During World War I and World War II, cigarettes were rationed to soldiers. During the second half of the 20th century, the adverse health effects of cigarettes started to become widely known and text-only health warnings became commonplace on cigarette packets. The United States has not yet implemented graphical cigarette warning labels, which is considered a more effective method to communicate to the public the dangers of cigarette smoking.[7] Canada and Australia, however, have both textual warnings and graphic visual images displaying, among other things, the damaging effects tobacco use has on the human body.

The cigarette has evolved much since its conception; for example, the thin bands that travel transverse to the "axis of smoking" (thus forming circles along the length of the cigarette) are alternate sections of thin and thick paper to facilitate effective burning when being drawn, and retard burning when at rest. Synthetic particulate filters remove some of the tar before it reaches the smoker.

Manufacturing

Commercially manufactured cigarettes are seemingly simple objects consisting mainly of a tobacco blend, paper, PVA glue to bond the outer layer of paper together, and often also a cellulose acetate–based filter.[8] While the assembly of cigarettes is straightforward, much focus is given to the creation of each of the components, in particular the tobacco blend, which may contain over 100 ingredients[9], many of them flavourants for the tobacco. A key ingredient that makes cigarettes more addictive is the inclusion of reconstituted tobacco, which has additives to make nicotine more volative as the cigarette burns.[1]

Paper

Main article: Cigarette paper

The paper for holding the tobacco blend may vary in porosity to allow ventilation of the burning ember or contain materials that control the burning rate of the cigarette and stability of the produced ash. The papers used in tipping the cigarette (forming the mouthpiece) and surrounding the filter stabilise the mouthpiece from saliva and moderate the burning of the cigarette as well as the delivery of smoke with the presence of one or two rows of small laser-drilled air holes.[10]

The burn rate of cigarette paper is regulated through the application of different forms of microcrystalline cellulose to the paper[11]. Cigarette paper is also specially engineered with different bands of porosity in fire-safe cigarettes to reduce its idle burning speed and allows it to self extinguish[12] Many states in the USA and as well as Canada is considering to require such papers as regulatory measure to reduce fire risks for cigarettes[13]. The paper is manufactured by mechanically altering the setting of the paper slurry[14]

Tobacco blend

Image:Cigaret tobacco.JPG
The tobacco part viewed from a cigarette

The process of blending, like the blending of scotch and cognac, gives the end product a consistent taste from batches of tobacco grown in different areas of a country that may change in flavour profile from year to year due to different environmental conditions.[15]

Modern cigarettes produced after the 1950s, although composed mainly of shredded tobacco leaf, use a significant quantity of tobacco processing by-products in the blend. Each cigarette's tobacco blend is made mainly from the leaves of flue-cured brightleaf, burley tobacco, and oriental tobacco. These leaves are selected, processed, and aged prior to blending and filling. The processing of brightleaf and burley tobaccos for tobacco leaf "strips" produces several by-products such as leaf stems, tobacco dust, and tobacco leaf pieces ("small laminate").[15] To improve the economics of producing cigarettes, these by-products are processed separately into forms where they can then be possibly added back into the cigarette blend without an apparent or marked change in the cigarette's quality. The most common tobacco by-products include:

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