Second-hand smoke may also be called environmental tobacco smoke (ETS), passive smoking or involuntary smoking. It is what smokers breathe out or the smoke from a burning cigarette, pipe or cigar. Many of us breathe in second-hand smoke in public places, such as around doorways of buildings, on patios and walking on the street. When you are near someone who’s smoking, you and everyone else around them are smoking too.
No amount of second-hand smoke is safe. Non-smokers exposed to second-hand smoke take in the same harmful chemicals as smokers. Studies show that even low levels of second-hand smoke exposure can be harmful. Every year, more than 800 Canadians who don’t smoke die from second-hand smoke.
Every time you smoke, the toxic chemicals from the smoke gets into everything around you, including dust, carpet, furniture, curtains, clothing, and other objects. The chemicals that stay around after the cigarette is out are referred to as third-hand smoke. The chemicals from third-hand smoke pollute the air and get into your lungs and body.
Second-hand smoke affects everyone’s health. Children, pregnant women, older people and people with heart or breathing problems should be especially careful to avoid second-hand smoke. Second-hand smoke contains many of the same chemicals that a smoker breathes in while smoking. Hundreds of these chemicals are toxic. More than 70 of them cause cancer.
The International Agency for Research on Cancer (an agency of the World Health Organization) has classified second-hand smoke as a known carcinogen. Being around second-hand smoke puts you at risk of developing lung cancer. It can also increase your risk for voice box (laryngeal) and throat (pharyngeal) cancers. Research also shows that there may be a link between second-hand smoke and breast cancer risk.
Exposure to second-hand smoke increases your risk for lung disease, heart disease, heart attacks and stroke. Second-hand smoke also makes you congested and causes you to cough. It can irritate your skin, eyes, nose and throat. Second-hand smoke can make allergies or breathing problems (like asthma) worse.
Even your pets are affected by second-hand smoke. Second-hand smoke has been linked to several types of cancer in dogs, cats and birds. Pets are more likely to develop cancer and other health problems if they live in a home with smokers. Third-hand smoke is dangerous for pets too. Dogs and cats lick third-hand smoke from their fur when they groom themselves. Birds also take in these toxic chemicals when they pick through their feathers.
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Children and second-hand smoke
No amount of second-hand smoke is safe. Babies and children are at risk of tobacco-related disease from second-hand smoke. According to the 2013 Canadian Tobacco, Alcohol and Drugs Survey (CTADS), 3.9% of children between the ages of 0 and 17 years were regularly exposed to second-hand smoke at home. This number is down slightly from the 4.5% reported in 2012.
Pregnancy, newborns and babies
Mothers who don’t smoke are healthier. They have easier pregnancies and labours, as well as faster recoveries after giving birth. Smoking during pregnancy can increase your risk of miscarriages, stillbirths and delivering the baby early.
When a pregnant woman smokes, her baby smokes too. During pregnancy, several chemicals in smoke and second-hand smoke can pass into the baby’s blood and affect how they develop. When a mother smokes or breathes in second-hand smoke, some of the toxic chemicals (such as tar and nicotine) pass directly into breast milk.
Third-hand smoke is also harmful to babies. Babies crawl or play on the floor and put things in their mouths. This means they take in more dust than adults, so they’re exposed to more third-hand smoke.
Health effects on children
Children are at greater risk of getting sick from second-hand smoke than adults. They breathe faster than adults. This means they breathe in more of the harmful chemicals from second-hand smoke. Children’s bodies are still growing and their immune systems are less developed than adults, so they are more likely to get sick.
Compared to children of non-smokers, children exposed to second-hand smoke are more likely to suffer from:
- coughing and wheezing
- painful ear infections
- asthma and other breathing problems
- bronchitis, croup and pneumonia
- sudden infant death syndrome (SIDS)
Second-hand smoke may even harm your child’s ability to read and do math. Children exposed to second-hand smoke tend to do less well in school than children from smoke-free homes.
Researchers have shown that exposure to second-hand smoke increases the risk of cancer in adults. Studies looking into the link between second-hand smoke and childhood cancer risk haven’t been as consistent.
Some studies have shown that having parents who smoke and being exposed to second-hand smoke before birth is a risk factor for a type of liver cancer in children called hepatoblastoma. Researchers also think there may be a link between parents smoking before their child is born and the risk their child will develop leukemia. But more evidence is needed to say that exposure to second-hand smoke before birth is a known risk factor for childhood leukemia.
Children who are exposed to second-hand smoke over time are more likely to develop lung cancer as an adult.
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Reducing your risk
Live smoke-free. If you smoke, get help to quit. Take steps to avoid second-hand smoke and make your home and car smoke-free. Opening a window or turning on a fan is not enough to clear the air.
In your home
Because Canadians spend most of their time indoors, air quality in the home is important. Think about how to make your home smoke-free. Talk about it with family and friends, and politely ask them to smoke outside. Let them know you are rejecting their smoking, not them.
Second-hand smoke can get into an apartment or condominium unit through shared vents and openings. It can also drift under doors and through cracks and air leaks around electrical outlets, plumbing and windows. You can help reduce second-hand smoke in your apartment or condo by installing special seals in electrical outlets. These are available at hardware stores. You can also install door sweeps and seal cracks around vents and windows with foam insulation to prevent smoke from entering your unit. Talk to your neighbours, landlord or condo association and work with them to reduce second-hand smoke.
If you have to smoke, always smoke outside, far away from children. Make sure you put out your cigarette before going near children. Clear away ashtrays to keep children from playing with cigarette butts. Never leave a lit cigarette, lighters or matches unattended.
In your car
Second-hand smoke is concentrated inside the small space of a car. This makes it more dangerous. The chemicals remain in the car, even when tobacco is no longer burning. You can help reduce exposure to second-hand smoke by not smoking in your car. Let your passengers know that your car is smoke-free. If you do smoke in your car, give it a good cleaning. Vacuum the upholstery and clean out the ashtray.
Away from home
Whenever possible, avoid places where you or your children can be exposed to second-hand smoke. Talk to your employer about ways of making your workplace smoke-free, if it isn’t already. When travelling, ask for smoke-free rooms. Support businesses that are smoke-free and support smoke-free bylaws or campaigns.
Work with daycare and school officials to make sure buildings and surrounding property are smoke-free. Support efforts to ban smoking in public places where children may be.
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