Secondhand smoke includes both the smoke from the end of a burning cigarette or cigar and also the smoke exhaled by the smoker. Secondhand smoke can also be called passive smoking, involuntary smoking, or environmental tobacco smoke. People may be exposed to secondhand smoke by members of their household or workplace, or in social settings. As a side note for those exposed to cigar smoke, because cigars contain more tobacco than cigarettes, and because they often burn for much longer, they give off greater amounts of secondhand smoke. Secondhand smoke can be harmful in many ways. It can cause premature death and disease in children and adults who do not smoke. Secondhand smoke is particularly harmful to children. Children exposed to secondhand smoke are at an increased risk of sudden infant death syndrome (SIDS), acute respiratory infections, ear problems, and more severe asthma. Smoking by parents causes breathing (respiratory) symptoms and slows lung growth in their children.
In addition, to all these health problems, exposure to secondhand smoke can increase a person's risk of developing lung cancer. Ten to fifteen percent of lung cancers diagnosed in never-smokers are attributed to secondhand smoking. This exposure has also been associated with increased risk for cancers of the mouth, throat, voice box, pancreas, bladder, kidney, cervix, and childhood leukemias.
Smoke-free workplaces, restaurants and bars have helped reduce unwanted exposure to secondhand smoke, but many people are still exposed in their homes. The EPA has tools for community groups and individuals for starting educational programs promoting smoke free homes or just creating a smoke free environment in their own home.