Passive smoking

Passive smoking means breathing in other people’s tobacco smoke. A smoker’s exhaled smoke is called exhaled mainstream smoke. The smoke drifting from their lit cigarette is called sidestream smoke. The combination of mainstream and sidestream smoke is called environmental tobacco smoke (ETS).

Most of the smoke that hangs in a room is sidestream smoke, which contains higher levels of cancer causing compounds than mainstream smoke. ETS is a common indoor pollutant. The fact that Australians spend about 90 per cent of their time indoors (on average) makes passive smoking a serious health hazard for both smokers and non-smokers.

Children are particularly at risk of adverse health effects from passive smoking. Workers in the hospitality industry are also at risk if they work in pubs and other enclosed spaces where patrons smoke.

Irritant effects
Tobacco smoke inside a room tends to hang in mid-air rather than disperse. Hot smoke rises, but tobacco smoke cools rapidly, which stops its upward climb. Since the smoke is heavier than the air, the smoke starts to descend. A heavy smoker who smokes indoors causes a permanent low-lying smoke cloud that other householders have no choice but to breathe.

Tobacco smoke contains around 4,000 chemicals, made up of particles and gases, about 60 of which are known to cause cancer. In 1992, the United States Environmental Protection Authority classified environmental tobacco smoke as a Group A carcinogen – one that causes lung cancer in humans. Compounds such as ammonia, sulphur and formaldehyde irritate the eyes, nose, throat and lungs. These compounds are especially harmful to people with respiratory conditions such as bronchitis or asthma. Exposure to environmental tobacco smoke can either trigger or worsen symptoms.

Health risks – unborn babies
Australian data indicates that about 20 per cent of women smoke during pregnancy, although this percentage appears to be going down. Both smoking and passive smoking can seriously affect the developing foetus.

Health risks for mothers who smoke during pregnancy include:

• Increased risk of miscarriage and stillbirth
• Increased risk of premature birth and low birth weight
• Increased risk of sudden infant death syndrome (SIDS)
• Increased risk of complications during the birth.

• Passive smoking is a risk factor in sudden infant death syndrome (SIDS or cot death).
• A child who lives in a smoking household for the first 18 months of its life has an increased risk (around 60 per cent higher) of developing a range of respiratory illnesses including croup, bronchitis, bronchiolitis and pneumonia. They are also more prone to getting colds, coughs and glue ear (middle ear infections). Their lungs show a reduced ability to function and slower growth.
• A child exposed to environmental tobacco smoke in the home is 40 per cent more likely to develop asthma symptoms. Estimates suggest that about eight per cent of childhood asthma cases are caused by passive smoking.

• Passive smoking increases the risk of heart disease. There is consistent evidence that non-smokers married to smokers have higher risks of coronary heart disease than those whose spouses do not smoke.
• Tobacco smoke makes the blood more ‘sticky’ and likely to clot. There is evidence that levels of the ‘good’ or protective blood cholesterol (called high density lipoprotein or HDL) are also reduced.
• Long term exposure to passive smoking may lead to the development of atherosclerosis (narrowing of the arteries). Just 30 minutes of exposure to environmental tobacco smoke can start this process.
• Non-smokers who suffer long term exposure to environmental tobacco smoke have a 20 to 30 per cent higher risk of developing lung cancer than non-smokers who are not exposed to passive smoke.
• The National Health and Medical Research Council (NHMRC) has estimated that 11 people who have never smoked die from lung cancer each year in Australia, and up to 77 people die from coronary heart disease, because they are exposed to smoke at home.
• There is increasing evidence that passive smoking can increase the risk of stroke among non-smokers.
• There is an increased risk of nose and sinus cancer.

• Make your home smoke-free. Some smokers think that limiting their smoking to one or two rooms is an effective measure, but tobacco smoke easily drifts through the rest of the house.
• Make sure that smokers who visit the house smoke their cigarettes outdoors, no matter what the weather. If they object or take offence, try calmly explaining the health risks of passive smoking, and point out that you simply want to protect the health of your family.
• Make your car smoke-free. The other occupants will still be exposed to tobacco smoke even if the windows are open.
• Don’t allow smoking in any enclosed space where your partner or children spend time – for example inside the garage, shed, cubby house, boat or caravan.
• Don’t take your children to smoky venues. If you do visit a smoky venue, always choose the non-smoking seating area (if there is an option).
• Make sure that all people who look after your children (for example, grandparents or babysitters) provide a smoke-free environment.
• For more information on living smoke-free, visit www.smokefree.org.au

• Your doctor
• Your chemist
• Quitline Tel. 137 848

• If a smoker can’t give up for their own health, perhaps the health of their partner or children will be a stronger motivation.
• Passive smoking increases the risk of respiratory illnesses in children, including asthma, bronchitis and pneumonia.
• People who have never smoked who live with smoking partners are at increased risk of a range of tobacco-related diseases including lung cancer, heart disease and stroke.

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