What you need to know about second-hand smoke

What is second-hand smoke?

Second-hand smoke is what smokers breathe out and into the air. It’s also the smoke that comes from a burning cigarette, cigar or pipe.

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

Every year, about 800 Canadian non-smokers die from second-hand smoke.

Person coughing from breathing in second-hand smoke

How second-hand smoke affects you

  • You risk developing lung cancer and other lung diseases.
  • You’re at a higher risk for heart attacks and stroke.
  • It can bother your skin, eyes, nose and throat.
  • If you have allergies or breathing problems (like asthma), second-hand smoke can make them much worse.

Find great tips to avoid or stop second-hand smoke in Live Free of Second-hand Smoke.

Person coughing from breathing in second-hand smoke
A pregnant woman breaking a cigarette

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
  • get sick more often than other babies
  • die from sudden infant death syndrome (SIDS)
  • have breathing problems like wheezing and coughing
  • develop ear infections
  • have chronic lung disease when they’re older
  • develop asthma, and their asthma will be worse
  • do less well in school, particularly in reading and math
A pregnant woman breaking a cigarette