Which cancer-causing chemicals are found in cigarette smoke?

Cigarette smoke is a complex mixture containing more than 4,000 chemical compounds, of which more than 60 are known carcinogens (cancer-causing substances).12

These harmful agents include:

• Tobacco-specific nitrosamines: Potent carcinogens unique to tobacco products.1
• Polycyclic aromatic hydrocarbons: A group of chemicals formed during the combustion of organic material.1
• Acetaldehyde: A chemical known to damage cellular DNA.31
• Benzene: A toxic industrial chemical found in tobacco smoke.3
• Formaldehyde: A substance often associated with tissue damage and cancer risk.3
• Cadmium: A toxic heavy metal.3
• 1,3-butadiene: A toxic gas.3

When these chemicals are inhaled, they can bind to and damage cellular DNA. If cells with this damaged genetic material survive and replicate, they can lead to the development of cancer. Because smoking causes persistent exposure to these agents, it is estimated to be responsible for 90 percent of all lung cancer cases and is a major cause of various other cancers, including those of the bladder, pancreas, larynx, oral cavity, and esophagus.14