Secondhand smoke is the combination of smoke emanating from the mouthpiece end of a cigarette or exhaled from the lungs (mainstream smoke) and smoke emanating from the ignited end of a cigarette (sidestream smoke).
According to the Centers for Disease Control and Prevention, National Cancer Institute, and American Lung Association:
- Secondhand smoke exposure is prevalent. 58 million people (1 in 4 nonsmokers) are exposed to secondhand smoke — this includes 2 out of every 5 children.
- Tobacco smoke contains harmful chemicals. There are 250 toxic chemicals in tobacco smoke, including 69 known cancer-causing agents (carcinogens).
- Inhaling secondhand smoke can lead to disease and premature death. Secondhand smoke may increase the risk of heart disease and can lead to health risks in children and pregnant women. Approximately 3,400 nonsmokers die each year of lung cancer caused by secondhand smoke exposure.
In recent years smoke-free legislation has greatly increased the number of public places, including workplaces, that are now smoke-free.