Tobacco
composition
otherwise wasted. During the manufacturing process of
reconstituted tobacco, a significant amount of additives
such as ammonia and humectants can easily be
introduced. Extra nicotine can also be added during the
‘nicotine-enriching process’.
The most effective nicotine delivery tool
Additives are all the chemicals added to the tobacco
products and tobacco derivatives. Sugar, flavorings
and humectants are the largest additives usediii. Other
chemicals, such as ammonia and pesticides, are used
in a smaller quantity. Additives are used for several
reasons including prolonging the shelf life; enhancing
the taste of tobacco to make the product more
desirable (e.g. flavorings, chocolate, sweeteners,
menthol); masking the smell and visibility of sidestream smoke and enhancing the ‘free’ delivery of
nicotine to the brain (e.g. ammonia) iii making it more
easily absorbed.
Tobacco products are categorised into smoked
(combustible) and smokeless (non-combustible)
tobacco. Smoking tobacco products include
manufactured cigarettes, roll-your-own, cigars and
pipes; smokeless tobacco products include chewing
tobacco and snuff.
Whether the products are combustible or noncombustible, all tobacco products are highly
engineered ‘packages’ to optimise the delivery of
nicotine into the brain. While nicotine alone is a highly
addictive substancei, many chemicals are added to
make tobacco more appealing and addictive.
Nicotine
Nicotine is an alkaloid that naturally exists in the
nicotiana tabacum plantsii. In preparation for
consumption, tobacco leaves are cured. This involves
drying out of leaves and aging them ready for
processing.
Nicotine can be rapidly absorbed into the bloodstream, especially under a high pH environment and/or
during combustioniii which releases nicotine. Nicotine is
highly addictive and acts in a similar way to drugs
such as heroine and cocainei. When absorbed into the
brain it elicits pleasant or rewarding effects as a result
of the release of dopamine and other
neurotransmitters. The body quickly develops an
increased tolerance after chronic exposure to nicotinei.
Reconstituted tobacco
Reconstituted tobacco is a paper-like sheet often
added to cigarettes and cigars. It is made of other
parts of the tobacco plant (ribs and stems) that are
Additives
In 1994, US tobacco companies released a list of 599
addictivesiv contained in cigarettes. In New Zealand,
there was a common list of over 350 known additives
in cigarettes between 1999 and 2006v. Although these
ingredients are approved for use as food additives,
their toxic effects have never been assessed on
tobacco products during the manufacturing process or
during consumption.
Tobacco dependence (addiction) is regarded as a
disease under the World Health Organization’s
International classification of disease (ICD-10)vi.
Exposure to the toxic effects of these ingredients is
magnified whenever nicotine is delivered more
efficientlyvii and thus increases the risks of tobaccorelated diseases.
Tobacco smoke
When a cigarette or cigar is burned, tobacco smoke is
released into the air either from the burning tips of
tobacco products (sidestream smoke) or through the
mouthpiece when puffs are taken (mainstream
smoke). Tobacco smoke comprises of over four
thousands chemical compoundsiv that are released as
airborne gases or particles; many are known to be
carcinogenic, irritants or toxic.
i
Gaseous compounds
Tobacco smoke contains between 400 to 500 gases,
including carbon monoxide, ammonia, formaldehyde,
hydrogen cyanide and dimethyl-nitrosamineviii.
Royal College of Physicians of London. 2000. Nicotine
Addiction in Britain. A report of the Tobacco Advisory Group of
the Royal College of Physicians.
http://www.rcplondon.ac.uk/pubs/books/nicotine/ (Retrieved:
12th November 2008)
ii
Tar
Tar is the sticky brown substance that stains smokers’
teeth, fingers and lungs. Up to 70 percent of the tar in
cigarettes remains inside the smokers lungs. Tar
contains many known carcinogens including tobaccospecific N-nitrosamines, aromatic hydrocarbons; heavy
metals such as lead, chromium and cadmium; as well
as radioactive substance polonium-210viii.
‘Low’ tar cigarettes
Nicotine and tar levels are assumed to be reduced by
the cellulose acetate filter at the end of the cigarette,
thus reducing the risks of many diseases. But the main
function of the filter appears to be making the products
more palatable to smokers and the actual health
benefits are yet to be proven. Cigarettes with filters
still kill half of their smokers.vii
A common way in which ‘light and mild’ cigarettes are
made is for manufacturers to put small vent holes into
the filter tip. The level of perforation in the cigarette
paper is deemed to reduce the levels of nicotine and
tar. Low tar cigarettes are wrapped with more porous
paper which dilutes the smoke and allegedly reduces
nicotine and tar level. When the smoke is inhaled, a
greater proportion of air combines with it to give the
impression of smoothness. When these cigarettes are
smoked by a machine the holes remain uncovered and
it will therefore read lower yields of tar. When smoked
by a person the fingers or the lips will cover the holes
making the cigarette behave like a full strength
product. Smokers will compensate the reduced amount
of nicotine in each puff by smoking more or inhaling
more deeply. A low tar cigarette is no safer than a high
tar cigarette.vii
Hoffmann, D. I. Hoffmann. 1998. Chemistry and Toxicology in
Smoking and Tobacco Control Monograph No. 9.
Bethesda,MD:US:National Cancer Institute. p. 55-104.
iii
Bates, C., Jarvis, M., Gregory, C., 1999. Cigarette engineering and
nicotine addiction in Tobacco additives. ASH UK.
iv
Martin M. 2004. Smoking cessation: What’s in a cigarette? The List of
Additives, A through C in About.com.
http://quitsmoking.about.com/cs/nicotineinhaler/a/cigingredients.htm?p
=1 (Retrieved: 5th November 2008)
v
Murray L. 2007. Tobacco returns for the 2006 calendar year. Report
to the Ministry of Health. Health New Zealand Ltd.
vi
ICD-10: international statistical classification of diseases and related
health problems: tenth edition. 2nd edition. Geneva:World Health
Organisation, 2004,
vii
World Health Organisation. 2006. Tobacco: deadly in any form or
disguise. Geneva. Switzerland.
viii
Hoffmann D, Hoffmann I. 2001. The Changing Cigarette: Chemical
Studies and Bioassays in Smoking and Tobacco Control Monographs
13. Bethesda,MD:US:National Cancer Institute. p159-192.