How dangerous is second-hand smoke?

Second-hand smoke is the inhaled smoke from the end of a smoker's burning cigarette as well as the smoke that the smoker exhales. Those who inhale second-hand smoke are exposed to nicotine, as well as harmful chemicals from a smoker's cigarette. This increases the risk of lung cancer, heart disease, asthma, emphysema, and eye and nasal irritation. Those at greatest risk include bar and service industry workers, pregnant women, and children of smokers. These children may become asthmatic, have chronic colds and coughs, be at increased risk for bronchitis or pneumonia, develop learning delays and behavioral problems, have ear infections, and/or develop high blood pressure.

Dr. Joseph I. Miller, MD
Cardiothoracic Surgeon

Second hand smokes carries almost the same risk as primary smoking. If you are around a smoker you should consider sending them outside or into a secluded space.

Eight hours of secondhand smoke is the equivalent of smoking 20 cigarettes, a pack of cigarettes. That leads to immune dysfunction and heart disease. Let me phrase it another way. When secondhand smoke was banned in Pueblo, Colorado, and in Scotland and in one town in Italy, the hospitalization rate of nonsmokers, that is of people who only got secondhand smoke by passing through smokers' smoke outside of buildings, etc., went down between 4 percent and 25 percent and death rates in nonsmokers went down the next year 2 percent or more in those three communities. That's pretty impressive.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Secondhand smoke is related to loads of fatal or life-threatening conditions. Annually, secondhand smoke causes about 3,000 cases of lung cancer in nonsmokers, who most likely get the disease because of the smoke around them. It's also linked to about 35,000 deaths from heart disease.

Babies exposed to secondhand smoke are at increased risk for sudden infant death syndrome (SIDS). And secondhand smoke increases the risk that a child will develop asthma, a chronic lung disease. No prizes for guessing what I'm going to recommend: Quit smoking today. But if you do keep smoking, step away from others when you puff.

Secondhand smoke is dangerous and can trigger cancer, asthma, and other illnesses. Smoking affects everyone.

Secondhand smoke is like taking a cigarette yourself. I can remember as a child that my mother who smoked would have cigarettes going in the car with the windows up. It was just like me smoking a cigarette as a 6-year-old so I encourage anybody who is around secondhand smoke to treat it like they are smoking themselves and to get away from it as soon as possible.

Irwin Isaacs
Psychology Specialist

There is no doubt that it is harmful to one’s health to breathe in second hand smoke. The degree of danger depends on the age and physical condition of the one breathing the second hand smoke.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.