Smoking and cancer

Cigarette smoke contains thousands of chemical compounds, many of which cause  damage that can lead to cancer. For example, some chemicals fix themselves to the cells’  DNA, causing mutations. see:

https://www.cancerresearchuk.org/about-cancer/causes-of-cancer/smoking-and-cancer/how-does-smoking-cause-cancer#tobacco10

https://www.cancerresearchuk.org/health-professional/cancer-statistics/risk/tobacco#heading-Zero

https://www.cancerresearchuk.org/about-cancer/causes-of-cancer/smoking-and-cancer/how-does-smoking-cause-cancer

How can I stop smoking?

https://www.cancerresearchuk.org/about-cancer/causes-of-cancer/smoking-and-cancer/how-do-i-stop-smoking