Tobacco and Public Health - TCSC Indonesia

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NICOTINE DOSING CHARACTERISTICS ACROSS TOBACCO PRODUCTS
area (Burton et al. 1992). Alkaloid levels increases as a plant matures, especially during
the period after topping. Marked increase of nicotine is generally associated with the
increased rate of nitrogen fertilization. Under favorable conditions, N. rustica produces
double the quantity of nicotine measured in ordinary tobacco (Tso 1990). The curing
and processing technologies (Peele et al. 1995; Wiernik et al. 1995), as well as the storage
conditions (Burton et al. 1989), also have a profound influence on the alkaloid content
in tobacco.
The wide variation of nicotine content in commercial tobaccos (from 0.17 to 4.93%;
Tso 1990) enables manufacturers to achieve, easily, desired nicotine delivery in a specific
product by tobacco blending. In the past, flue-cured tobaccos were used exclusively for
cigarettes in the United Kingdom, Finland, Canada, Japan, China, and Australia.
Air-cured tobaccos were the preferred choice for cigarettes in France, southern Italy,
some parts of Switzerland and Germany, and South America. Cigarettes made from
sun-cured tobacco are smoked predominantly in Greece and Turkey. In the US, cigarettes
are made by blending flue-, air-, and sun-cured tobaccos as well as reconstituted
tobacco sheets. Currently, the American-blend cigarette is gaining market share
worldwide (Hoffmann and Hoffmann 2001).
Apart from its well-documented effects on the central nervous and cardiovascular
system (Benowitz 1998a, b), nicotine plays an important role in tobacco-associated
carcinogenesis. Nicotine is the major source of the three carcinogenic tobacco-specific
N-nitrosamines (TSNA): 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK),
4-methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), and N′-nitrosonornicotine
(NNN) (Hoffmann et al. 1994). The minor secondary amine tobacco alkaloids such as
nornicotine, anatabine, and anabasine also give rise to corresponding N-nitrosamines:
NNN, N′-nitrosoanatabine and N′-nitrosoanabasine, respectively. NNK and NNAL
are very potent procarcinogens, which, upon metabolic activation induce lung cancer
in all laboratory animals tested, regardless of dose and the route of administration
(Hecht 1998, 1999). NNN, in addition to inducing lung cancer in mice, is predominantly
responsible for esophageal and nasal tumors in rats. The data emerging from
testing the potential impact of nicotine itself on pulmonary carcinogenesis suggest that
chronic non-neoplastic lung diseases such as bronchitis, bronchiolitis, chronic
obstructive pulmonary disease, emphysema, and asthma, are highly associated with
both active and involuntary smoking and may pose an additional risk factor for lung
cancer (Schuller 1998). Most recently, nicotine has been reported to be a possible
promoter of cancer progression in human lung cells grown in the laboratory
(West et al. 2003).
Nicotine content in tobacco products
The most commonly used tobacco products worldwide are cigarettes, both manufactured
and hand made (a.k.a. roll-your-own). However, there are many countries in the world,
especially in South Asia, where smokeless tobacco use is a significant part of the overall