Secondhand Smoke

When you are exposed to smoke in the environment it is called secondhand smoke. Secondhand smoke is a combination of two types of smoke, sidestream and mainstream smoke. Mainstream smoke is the smoke exhaled by a person who is smoking. Mainstream cigarette smoke is a mixture of over 4,000 chemicals, 40 of which cause cancer (carcinogens) in humans. Sidestream smoke is the smoke from the end of a burning cigarette. Sidestream smoke contains all of these same carcinogens.

Many studies have looked at the results of exposure to indoor air pollution and secondhand smoke. Studies by the Environmental Protection Agency (EPA) show that indoor levels of many pollutants are often much higher than outdoor levels. These levels of indoor air pollutants are of particular concern because most people spend about 90 percent of their time indoors, either at home or in the workplace. In a report released in 1993, the Environmental Protection Agency (EPA) declared, "the widespread exposure to environmental tobacco smoke in the United States represents a serious and substantial public health impact." The EPA concludes that in adults, secondhand smoke is a Class A carcinogen. It is responsible for approximately 3,000 lung cancer deaths every year in U.S. non-smokers.

Additional reports have concluded that secondhand cigarette smoke is also associated with a higher risk of heart disease in non-smokers. Studies show that it causes approximately 53,000 deaths from heart disease a year in non-smokers.

Learn who is at greater risk of having severe problems associated with secondhand smoke.

Learn steps to avoid secondhand smoke.

This information has been approved by David Tinkelman, MD (February 2006).