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Anatomy of a Cigarette

Conventional Cigarette
Note: This virtual cigarette does not represent a particular brand but describes the structure of many of the most popular brands of cigarettes on the market.

Tobacco
Only a portion of the tobacco inside a cigarette comes from the leaf of a tobacco plant. A significant amount of the shredded brown innards of most modern cigarettes is a paper product called "reconstituted tobacco" or "homogenized sheet tobacco," which is made from a pulp of mashed tobacco stems and other parts of the tobacco leaf that would otherwise go to waste. Manufacturers spray and impregnate reconstituted tobacco paper with nicotine and other substances lost during the process, along with as many as 600 chemical additives. These include several that may come as a surprise, such as ammonia, which aids in the delivery of nicotine, and chocolate, which masks the bitter taste of tobacco. Finally, the 'recon' is sliced to resemble shredded leaf tobacco.

In addition to reconstituted tobacco, cigarette companies pack cigarettes with so-called puffed tobacco (also called "expanded tobacco"), which allows them to produce more cigarettes per pound of tobacco grown with lower levels of tar particles in the smoke. Manufacturers saturate this tobacco, which they make from the leaf of the plant, with freon and ammonia gases and then freeze-dry it. This process expands the tobacco, increasing its volume to at least double its natural state.

Paper wrap
Though seemingly innocuous, cigarette paper is largely responsible for the rate at which a cigarette burns and the amount and density of the smoke it produces. The paper displays a pattern of concentric circle striations called "burn rings." The burn rings correspond to two different thicknesses in the paper, which serve to precisely control the speed at which the cigarette burns, slowing it automatically when the smoker is not inhaling in order to prolong the cigarette's consumption and speeding it up as the smoker takes a drag so as to maximize smoke intake. In addition, like the tobacco, the cigarette paper contains a host of chemicals, among them titanium oxide, which accelerates and maintains burning so the cigarette does not go out and the smoke is delivered evenly with each puff. These chemicals have contributed to many cigarette-caused fires, a problem that some manufacturers have not addressed until recently.

Filter
The filter cigarette was a specialty item until 1954, when manufacturers introduced it broadly following a spate of speculative announcements from doctors and researchers concerning a possible link between lung diseases and smoking. Reacting to smokers' voiced fears and sudden reduced cigarette consumption, cigarette companies, by altering the filter's structure and materials, began making competing claims about how low their brands' tar and nicotine levels were.

Some cigarettes today boast the inclusion of a "charcoal filter" in addition to the more common dense, synthetic fiber filters seen in almost all filter cigarettes. Manufacturers claim that charcoal filters, which contain bits of charcoal embedded within the fiber filters, reduce certain toxins in the smoke. But no evidence exists that these cigarettes are significantly less dangerous for the user.

Most filter cigarettes also bear ventilation holes punched around the circumference of the filter tip. (Regular cigarettes might feature one ring of ventilation holes, while light and ultra-light cigarettes of the same brand might have two or more rings.) These tiny holes, which you can see by holding the unrolled paper up to a bright light, can allow enough fresh air into the smoke that such cigarettes can test quite low in tar and nicotine levels when smoked by machines, which do not cover the holes. However, smokers' fingers or lips often cover some of these holes as they puff, giving them much higher doses of tar and nicotine than advertised. According to critics of the tobacco industry, the holes create a flexible dosing system that allows addicted smokers to maintain the tar and nicotine levels they crave while believing they are receiving lower, safer doses.

'Safer' Cigarettes

Note: In the past 25 years, major U.S. cigarette manufacturers have tried to develop reduced-hazard cigarettes. The brands below are just two of the many 'safer' cigarette prototypes.

Eclipse
Eclipse

In 1994, R.J. Reynolds began testing its Eclipse smokeless cigarette with consumers in select U.S. markets. Most scientists and health professionals agree that the combustion of tobacco creates most of the toxins in a typical cigarette. The presumed relative safety of Eclipse, which from a distance looks like a conventional cigarette, rests on the fact that only a small amount of the tobacco inside it actually burns. Instead, when a smoker lights a charcoal tip on the end of the cigarette, a column of processed tobacco laced with glycerin and flavors heats up. The warmed glycerin produces a smoke-like vapor, which carries nicotine released by the heat into the lungs. Because of the burning charcoal tip, carbon monoxide remains a constituent of the smoke, and overall toxin levels increase when the tip burns hot from heavy smoking.

It remains to be seen how well Eclipse will sell in the U.S. and, with further testing, whether or not it will live up to the claim that it may be a safer smoke. One benefit of Eclipse is that it significantly reduces harmful secondhand smoke.

Accord
Accord

In certain markets in the U.S. and Japan, Philip Morris is testing its version of a 'safer' cigarette, Accord. On the market since 1998, Accord includes two elements, a cigarette-like roll of tobacco (which cannot be conventionally burned) and a battery-powered heating device. The smoker inserts the special cigarette into a hole in the pager-sized heater and smokes the cigarette in conjunction with the heater. A microchip inside the heater controls each puff of the cigarette, delivering a specific amount of heated tobacco vapor to the smoker each time he or she takes a drag.

Very little of the tobacco inside the Accord cigarette actually burns, so neither ashes nor appreciable amounts of secondhand smoke result. At the top of the device, an LCD screen turns on when the smoker inserts an Accord cigarette, and as the smoker takes a drag, it reads out how many of a total of seven puffs remain in the cigarette. This high-tech smoking system costs an initial $40, which buys the consumer a carton of special Accord cigarettes, the electronic device, and a battery charger for renewing the heater after each pack of the special cigarettes.