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Smoking causes
about 35% of all cancer deaths in Singapore. There is strong
evidence from laboratory and population studies to identify
the smoking of tobacco as the single greatest cause of lung
cancer in the world. Cigarette smoking also contributes to
the risk of developing most cancers of the mouth, throat,
oesophagus and stomach. Smoking is strongly linked to the
development of liver, bladder and kidney cancers. Smoking
can also cause stroke and heart disease.
Every cigarette contains over
4000 types of chemicals. 400 of them are poisonous to our
health and about 40 of them are cancer causing! The 'tar'
component of cigarette smoke consists of many carcinogens
such as:
arsenic, carbon monoxide, nitrogen oxides, hydrogen cyanide
methanol, ammonia, and formaldehyde. These cancer-causing
substances stick to the lining of the respiratory tract and
lungs, and directly attack and damage living tissues. They
bind directly to the DNA, which becomes damaged. This starts
a mutation process where normal cells change into deadly tumours.
Cigarette smoke also destroys the natural defense of millions
of lung cells increasing their potential of developing cancer.
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