What you need to know about second-hand smoke

What is second-hand smoke?

Second-hand smoke is what people breathe out and into the air when they smoke. It’s also the smoke that comes from a burning cigarette, cigar or pipe. When you’re around someone who smokes, you breathe in second-hand smoke.

Second-hand smoke has the same toxic chemicals in it as the tobacco smoke breathed in by a person who smokes. More than 70 chemicals in second-hand smoke have been shown to cause cancer in human studies or lab tests.

Any exposure to second-hand smoke can be harmful to your health.

How second-hand smoke affects you

Adults who are exposed to second-hand smoke are more likely to:

develop lung cancer or another lung disease
have a higher risk for a heart attack or stroke
have irritated skin, eyes, nose and throat
develop worsened allergies or breathing problems like asthma

Person coughing from breathing in second-hand smoke

How second-hand smoke affects babies and children

Babies and children of parents who smoke are more likely to:

weigh less than normal at birth or be born prematurely
die from sudden infant death syndrome (SIDS)
have breathing problems like wheezing and coughing
develop ear infections
have lung infections
develop asthma that is more likely to be severe

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