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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. So if you’re sitting beside someone who’s smoking, you and everyone else around you are smoking too.

No amount is safe

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.

Being around second-hand smoke puts you at risk of developing lung cancer and other lung diseases. You’re also 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.

  • What is third-hand smoke?

    When a person smokes, the toxic chemicals from second-hand smoke travel through the air and land on carpets, furniture, curtains and other surfaces. They even land on any dust that’s in the room. These chemicals stay around after the cigarette is out – this is called third-hand smoke.

    People who smoke have third-hand smoke on their clothing, skin and hair – that’s why they smell like smoke even when they’re not smoking. And it’s why you smell like smoke after you’ve been around smokers.

  • Second-hand smoke hurts babies and children

    Babies who were around second-hand smoke before they were born can weigh less than normal at birth. This is because chemicals in second-hand smoke affect how they grow and develop. And if a new mother smokes, some chemicals such as nicotine go directly from her breast milk to her baby. Babies who breathe in second-hand smoke are more likely to get sick than other babies and to die from sudden infant death syndrome (SIDS).

    Babies crawl on the floor and often put things in their mouths. This means they take in more dust than adults and in turn more third-hand smoke.

    Children’s bodies are still growing, and they breathe faster than adults. This means they breathe in more harmful chemicals if they’re around second-hand smoke. Plus, their immune systems are less developed and can’t protect them as well.

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

    •   have breathing problems like wheezing and coughs
    •   develop ear infections
    •   have chronic lung disease when they’re older
    •   develop asthma, and their asthma will be worse

    Second-hand smoke may even harm the ability of your children and teens to read and do math. Children who are around second-hand smoke tend to do less well in school than children in smoke-free homes.

  • Second-hand smoke hurts pets

    Pets are more likely to develop cancer and other health problems if they live in a home with smokers. Second-hand smoke has been linked to several types of cancer in dogs, cats and birds.

    Pets lick third-hand smoke from their fur when they groom themselves. So do birds, when they pick through their feathers. This grooming adds to their cancer risk, especially for cats.

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Help for smokers trying to quit

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It’s okay to need help to quit smoking. The Canadian Cancer Society is here to support people who are ready to quit and even those people who aren’t ready.

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