Multiple things; mostly the chemicals that are added by the tobacco companies to enhance their products. Plus the fact when you inhale anything into your lungs you irritate them - causing damage.
The tar and poisonous gases produced as combustion products (smoke) are inhaled into the lungs, where they damage the cells, alveoli, that exchange oxygen in the lungs. This can cause tissue death, as in emphysema, or trigger mutations that grow into useless tissue, which is cancer.
It is mostly just the tobacco. First, tobacco is often allowed to ferment, and the fermentation can create carcinogens. Then there may be carcinogenic additives. Then there is the smoke that is produced by burning the tobacco and the paper. Burning things often create carcinogens.
Scientists are unsure, it may be the tar, it may be the fertilizer or it may be the burning process.
cigarette smoke contains 69 chemicals that are known to cause cancer.some include:tar,arsenic,benzene,cadmium,and formaldehyde.
Cigarette smoke contains a substance generally known as tar, but known to chemists as polycyclic aromatic hydrocarbons, which causes cancer.
When cigarettes burn, there is a combustion byproduct that is commonly known as tar; chemists know it as polycyclic aromatic hydrocarbons. That is what causes lung cancer.
nicotine and tar also carbon monoxide
it's the tar, since it's a carcinogen
Nicotine
Over 1,000 different substance all in them
carcinogen
The adds by cigarette companyhave been banned as it causes cancer and to warn the public.
While it's hard to determine exactly what's in tar, it's clear that it causes most of the bad health effects of tobacco: Cancer.
because a PART of our body gets rotten then it causes us cancer.
Cigarette produces a certain amount of a substance called tar in our lungs which causes cancer. After an year this tar becomes so much in amount that it can cause any disease in our body
A somewhat satirical synonym for cigarette is cancer stick.
Lung Cancer or Heart Disease or Strokes and a variety of other cancers
That would be the nicotine in the cigarette. this answer sucks
lung cancer
cancer sticks