Not all cigarettes are the same. Smokers around the world prefer many different tastes and strengths and we aim for excellence in every step of manufacturing.
Cigarette design is more complicated than it may seem. We work to understand the preferences of adult consumers and to design cigarettes to meet them. It’s the preferences of adult consumers that guide our blends – the mix of tobaccos used – and we work to ensure that these grades are available long-term to keep the tastes of the products consistent.
Food-type ingredients and flavorings are added to some types of cigarettes – typically American style blends – to balance the natural tobacco taste, replace sugars lost in curing, and give individual brands their characteristic flavor and aroma. Other ingredients control moisture, protect against microbial degradation, and act as binders or fillers.
Nicotine is not added in making cigarettes.It occurs naturally in all varieties of tobacco plants.
The filter, paper and level of filter ventilation are all chosen to affect the sensory strength and smoke yield of the cigarette. At each stage, there is constant quality control and testing.
Main parts of a cigarette
Cigarettes have four basic components:
- The tobacco rod
- The cigarette paper around the tobacco rod
- The filtration zone
- The filter and tipping around the filtration zone.
The tobacco in the rod includes tobacco lamina (the flat part of the tobacco leaf), tobacco stem (midribs of the leaf), and expanded lamina.
The cigarette paper includes paper and adhesive.
The filter is made mainly from cellulose acetate fibres, known as tow. Cellulose acetate is derived from wood pulp. The fibres are bonded together with a hardening agent, triacetin plasticizer, which helps the filter to keep its shape. The filter is wrapped in paper and sealed with a line of adhesive. Sometimes charcoal is added to filters.
The tipping paper includes paper and adhesive.
Design adjustments achieve different strengths and tastes, and can reduce smoke yields of various smoke components, as measured by a standardised machine method.
What happens when a cigarette burns?
To understand cigarette design, it helps to know how a cigarette burns. It is the combustion process - the burning of the cigarette - that produces tar. If hay were burned instead of tobacco, it would also produce a type of tar. When an item burns, it produces tiny particles mixed with gases – this is smoke. A cigarette filter traps some of these particles.
When a smoker puffs on a cigarette, whole smoke, including both fine particles and gases, is sucked through the tobacco rod and the filter. Gases pass through the filter, and some particles are trapped in it. It is this particulate matter, minus nicotine and water, that is called tar.
Smoke has over 4,000 constituents, many of them also found in the air we breathe and our food. These constituents include the emissions listed on packs, such as tar, nicotine and carbon monoxide. Water vapour is also produced by the combustion, because the burning of any organic material breaks down the chemical components and produces water.
The filter tips used in our cigarettes are biodegradable over a period of between a month and three years, depending on environmental conditions. Although the British American Tobacco Group is researching more rapid breakdown, at present it knows of no practical way of making consumer-acceptable filters that would degrade so quickly that they would not cause short-term littering problems.
We believe the best way to reduce potential litter problems is for consumers to dispose of filters and cigarette packs in a responsible way.
Health risks of smoking
Smoking poses real risks of serious diseases. That’s why the British American Tobacco Group is working to develop products that may be recognised as less harmful. For more about the health risks of smoking and the Group’s harm reduction efforts, see Health and science.