Tobacco and Public Health - TCSC Indonesia

494
SMOKING AND LUNG CANCER
Small increased risks such as this are below that which can be reliably detected by
epidemiological methods and the exposure assessment in these studies is poor. The use
of biomarkers for analysing and quantifying the role of ETS is much more complex for
cancer than asthma, given the much longer interval between exposure and clinical
manifestation of the disease. The critical reviewer could find shortcomings in the
majority of the published studies of ETS and lung cancer. However, as was recognized
by an IARC Working Party (IARC 1986) given current knowledge of the chemical constituents
of both side stream and mainstream smoke, of the materials absorbed during
passive smoking and of the quantitative relationships between dose and effect that are
commonly observed from exposure to carcinogens, it could be concluded that passive
smoking gives rise to some risk of lung cancer. The great deal that is known about the
carcinogenic effects of active smoking (IARC 1986) has undoubtedly bolstered the
interpretation of the epidemiological data on passive smoking.
Despite nearly half a century of careful epidemiological study and the scientific
certainty that tobacco is carcinogenic there is still a need to quantify the risks of low
level exposure.
Public health failure, 1960s onwards
It has been clear for the entire second half of the twentieth century that cigarette smoking
causes lung cancer. Current low levels of smoking among physicians and research
scientists, in many countries, have led many of them unconsciously to overlook tobacco
smoking as an important cause of cancer (Boyle 1993b). There is, however, a very substantial
body of evidence from many sources which indicates the carcinogenicity of
tobacco smoking. Not only does cigarette smoking greatly increase the risk of lung
cancer in smokers, but the risk of oral cavity cancer, larynx cancer, oesophageal cancer,
bladder cancer, pancreas cancer, cervix cancer, stomach cancer, kidney cancer, and
colorectal cancer are also increased (Boyle 1997).
There is at present a worldwide epidemic of tobacco-related diseases: not only does
smoking cause increased levels of many different common forms of cancer, but it
also increases the risk of cardiovascular disease. Deaths from lung cancer, the cancer
site most strongly linked to cigarette smoking, have increased in Japan by a factor of
10 in men and 8 in women since 1950. In central and eastern Europe, more than
400 000 premature deaths are currently caused each year by tobacco smoking. In young
men in all countries of central and eastern Europe, currently there are levels of lung
cancer which are greater than anything seen before in the western countries and these
rates are still rising. In Poland, a country severely hit by the tobacco epidemic, lifeexpectancy
of a 45-year-old man has been falling for over a decade now due to the
increasing premature death rates from tobacco-related cancers and cardiovascular
disease (Zatonski and Boyle 1996). Tragically, cigarette smoking is still increasing
in central and eastern Europe and also in China, where an epidemic of tobacco-related