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Health Education

Alcohol, Tobacco, and Other Drugs

Secondhand Smoke

In recent years, universities, counties, states, and even countries have placed restrictions on public smoking to eliminate exposure to secondhand smoke (SHS). The scientific community has shown that there is no safe level of exposure to secondhand smoke, which makes SHS exposure a serious public health problem.

What is secondhand smoke?

Secondhand smoke comes from two places: smoke exhaled by the person who smokes, and smoke from the end of a burning cigarette. When a cigarette is burning on its own it burns at a lower rate causing incomplete combustion and dirtier smoke than the mainstream smoke a smoker inhales. Secondhand smoke is not filtered like most cigarettes so none of the chemical levels are reduced. Note: Non-smokers AND smokers are exposed to secondhand smoke!

Secondhand smoke contains more than 4000 chemicals, including many carcinogens (such as formaldehyde, cyanide, benzene, asbestos, arsenic, carbon monoxide, and methane). Secondhand smoke is classified as a Group A carcinogen by the EPA, meaning that SHS is known to cause cancer in humans.

Secondhand smoke is the third leading cause of preventable death, killing more than 53,000 individuals in the United States each year. In addition to several types of cancers (including lung, cervical, and nasal sinus cancers), SHS exposure also causes heart disease, asthma, stroke, coughing, wheezing, colds, and numerous other deleterious health effects.

Don't I have to breathe in a lot of secondhand smoke before anything bad will happen?

No, even a little SHS is dangerous. While some of the conditions mentioned above take years to develop, each time you are exposed to SHS you are contributing to the risk of developing one of those conditions. Just 5 minutes of exposure to secondhand smoke stiffens the aorta as much as if you had smoked a cigarette yourself. This causes your heart to work harder to pump blood throughout your body. Five minutes of exposure here and there can have serious consequences and contribute to risk of heart attack or development of heart disease.

An immediate danger of secondhand smoke exposure is that it may trigger an asthma attack. Every time a person with asthma walks by a smoker or enters a smoke-filled room, he or she is at risk for an asthma attack, which could be fatal.