Modern 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. While the assembly of cigarettes is straightforward, much focus is given to the creation of each of the components, in particular the tobacco blend. A key ingredient that makes cigarettes more addictive is the inclusion of reconstituted tobacco, which has additives to make nicotine more volatile as the cigarette burns. [edit]Paper Main article: Rolling 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 stabilize 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. According to Simon Chapman, a professor of public health at the University of Sydney, the burning agents in cigarette paper are responsible for fires and reducing them would be a simple and effective means of dramatically reducing the ignition propensity of cigarettes. Since the 1980s, prominent cigarette manufacturers such as Philip Morris and R.J. Reynolds developed fire-safe cigarettes but did not market them.[citation needed] The burn rate of cigarette paper is regulated through the application of different forms of micro crystalline cellulose to the paper. Cigarette paper has been specially engineered by creating bands of different porosity to create "fire-safe" cigarettes. These cigarettes have a reduced idle burning speed which allows them to self-extinguish. This fire-safe paper is manufactured by mechanically altering the setting of the paper slurry. New York was the first U.S. state to mandate that all cigarettes manufactured or sold within the state comply with a fire safe standard. Canada has passed a similar nation-wide mandate based on the same standard. All U.S. states are gradually passing fire-safe mandates. European Union wishes to ban in 2011 cigarettes that are not fire-safe. According to a study made by European Union in 16 European countries, 11,000 fires were due to people carelessly handling cigarettes between 2005 and 2007. This caused 520 deaths and 1600 people injured.[34] [edit]Tobacco blend Leones Africanos brand cigarettes from the mid 20th century, part of the permanent collection of the Museo del Objeto del Objeto. The process of blending gives the end product a consistent taste from batches of tobacco grown in diffe

ent areas of a country that may change in flavor profile from year to year due to different environmental conditions.[35] 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").[35] 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: Blended leaf (BL) sheet: a thin, dry sheet cast from a paste made with tobacco dust collected from tobacco stemming, finely milled burley-leaf stem, and pectin.[36] Reconstituted leaf (RL) sheet: a paper-like material made from recycled tobacco fines, tobacco stems and "class tobacco", which consists of tobacco particles less than 30 mesh in size (~0.599 mm) that are collected at any stage of tobacco processing.[37] RL is made by extracting the soluble chemicals in the tobacco by-products, processing the leftover tobacco fibers from the extraction into a paper, and then reapplying the extracted materials in concentrated form onto the paper in a fashion similar to what is done in paper sizing. At this stage ammonium additives are applied to make reconstituted tobacco an effective nicotine delivery system. Expanded (ES) or improved stems (IS): ES are rolled, flattened, and shredded leaf stems that are expanded by being soaked in water and rapidly heated. Improved stems follow the same process but are simply steamed after shredding. Both products are then dried. These two products look similar in appearance but are different in taste.[35] In recent years, the manufacturers' pursuit of maximum profits has led to the practice of using not just the leaves, but also recycled tobacco offal and the plant stem.[38] The stem is first crushed and cut to resemble the leaf before being merged or blended into the cut leaf.[39] According to data from the World Health Organization,[40] the amount of tobacco per 1000 cigarettes fell from 2.28 pounds in 1960 to 0.91 pounds in 1999, largely as a result of reconstituting tobacco, fluffing and additives. A recipe-specified combination of brightleaf, burley-leaf and oriental-leaf tobacco will be mixed with various additives to improve its flavours.