SummaryRead the full fact sheet
- Passive smoking means breathing in other people’s tobacco smoke.
- Passive smoking increases the risk of respiratory illnesses in children, including asthma, bronchitis and pneumonia.
- If you live with someone who smokes, you have a higher risk of diseases such as lung cancer, heart disease and stroke.
- Stopping smoking will not only make you healthier, but will also improve the health of your partner, children or other household members.
- If you are not ready to stop, making your home and car totally smoke-free is the next best way to protect your family from second-hand smoke.
- In Victoria, it is illegal to smoke in cars carrying people under 18 years of age.
Passive smoking means breathing in other people’s tobacco smoke. The smoke drifting from a lit cigarette plus the smoke breathed out by a smoker is called second-hand smoke or environmental tobacco smoke.
Second-hand smoke is a serious health risk for both those who smoke and those who do not. Children are particularly at risk of serious health effects from second-hand smoke.
Tobacco laws in Victoria
- in most indoor workplaces
- within the grounds of, and at and within 4 metres of an entrance to, all Victorian childcare centres, kindergartens (or preschools) and primary and secondary schools
- at and within 4 metres of an entrance to children’s indoor play centres and Victorian public premises (all public hospitals and registered community health centres, and certain Victorian Government buildings)
- in cars carrying people who are under 18 years of age
- at all of Victoria's patrolled beaches within 50 metres of a red and yellow flag
- within 10 metres of outdoor children's playground equipment
- within 10 metres of outdoor skate parks
- within the outdoor areas of all public swimming pool complexes
- within 10 metres of outdoor sporting venues during under 18s events and training sessions
- on public transport
- in all areas of train stations, covered bus shelters, raised platform tram stops and all tram stop shelters
- on the grounds of prisons
- at underage music or dance events
- in all outdoor dining areas where food (other than pre-packaged food or uncut fruit) is provided on a commercial basis
- at certain food fairs and organised events
- in outdoor areas that local councils have made smoke-free.
Toxic effects of passive smoking
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 person who smokes heavily indoors creates a low-lying smoke cloud that other householders have no choice but to breathe.
Tobacco smoke contains around 7,000 chemicals, made up of particles and gases, over 70 of which are known to cause . Second-hand smoke has been confirmed as a cause of by several leading health authorities.
Chemicals in second-hand smoke such as ammonia, sulphur and formaldehyde damage the eyes, nose, throat and lungs. These compounds are especially harmful to people with lung conditions such as or . Exposure to second-hand smoke can trigger or worsen symptoms.
Health risks of passive smoking – pregnant women and unborn babies
When a pregnant woman breathes in any tobacco smoke, her unborn baby is exposed to the chemicals in the smoke too. About 10% of Australian women smoke during pregnancy. Both smoking and passive smoking can seriously affect the developing baby.
- and low birth weight
- , which includes sudden infant death syndrome (SIDS) and fatal sleep accidents
When a non-smoking pregnant woman is exposed to second-hand smoke in the home – for example, if her partner smokes – it increases the risk for:
- early birth
- still birth
- low birth weight.
Active smoking by men can damage their sperm. Some health problems may be due to a non-smoking mother breathing in second-hand smoke, or sperm damage from the father’s tobacco use, or both. These include:
Health risks of passive smoking – children
Children are especially vulnerable to the damaging effects of second-hand smoke. Some of the many health risks include:
- Passive smoking is a cause of , which includes sudden infant death syndrome (SIDS) and fatal sleep accidents.
- A child who lives in a smoking household for the first 18 months of their life has an increased risk of developing a range of illnesses of the lung, including bronchitis, and . They are also more prone to coughs, and glue ear (). Their lungs are weaker and do not grow to their full potential.
- A child exposed to second-hand smoke in the home is more likely to develop asthma symptoms, have more and use more often and for a longer period.
- School-aged children of people who smoke are more likely to have symptoms such as cough, phlegm, wheeze and breathlessness.
- Children of people who smoke have an increased risk of , which can sometimes cause disability or death.
Health risks of passive smoking – partners who have never smoked
People who have never smoked who live with people who do smoke are at increased risk of a range of tobacco-related diseases and other health risks, including:
- – second-hand smoke affects your blood vessels in several ways:
- It makes the blood more ‘sticky’ and likely to clot.
- Passive smoking is associated with lower levels of antioxidant vitamins in the blood.
- Just 30 minutes of passive smoking can affect how your blood vessels regulate blood flow, to a similar degree to that seen in people who smoke.
- Passive smoking over a long time may lead to the development of atherosclerosis (narrowing of the arteries by fatty streaks).
- Lung cancer – people who are exposed to second-hand smoke over a long time have a 20 to 30% higher risk of developing lung cancer.
- There is increasing evidence that passive smoking may increase the risk of nasal sinus cancer, , , larynx cancer, long and short-term respiratory symptoms, loss of lung function, and among people who do not smoke.
Your family and friends – a good reason to stop smoking
When you stop smoking, you are not only doing great things for your own health, but for your loved ones.
- You will protect your partner, children or other household members from becoming ill from second-hand smoke.
- You will have more energy and time to spend with your kids.
- You will save a lot of money for you and your family.
- You are your child’s first role model – parents who stop smoking reduce the likelihood that their children will take up smoking later in life.
What are your reasons to have a go at quitting?
Protecting others from second-hand smoke
If you smoke but you are unwilling or unable to stop immediately, there are various ways to help protect the health of the people you live with. Suggestions include:
- Make your home totally smoke-free. Always smoke outdoors and shut windows and doors so smoke doesn’t drift inside. Limiting your smoking to one or 2 rooms will not protect your family – tobacco smoke can easily drift through the rest of the house.
- Make sure that visitors to your house smoke outdoors – that includes shisha as well as cigarettes.
- Make your car totally smoke-free. The other occupants will still be exposed to tobacco smoke even if the windows are open. In Victoria, it is illegal to smoke in cars carrying people who are under 18 years of age.
- Don’t allow smoking in any enclosed space where people who do not smoke spend time – for example, in the garage, shed, cubby house, boat or caravan.
- Try to avoid taking children to outdoor areas where people are smoking and you can’t easily move away.
- Make sure that all people who look after your children provide a smoke-free environment.
Where to get help
- , 2019, Quit Victoria.
- , 2014, US Department of Health and Human Services.
- , 2018, Quit Victoria.
- Campbell M, Ford C, Winstanley M 2020, ‘’, in Greenhalgh E, Scollo M and Winstanley M (eds), Tobacco in Australia: Facts and issues, Cancer Council Victoria.
- , 2020, in Greenhalgh E, Scollo M, Winstanley M, (eds), Tobacco in Australia: Facts and issues, Cancer Council Victoria.
- , 2020, Australian Institute of Health and Welfare, Perinatal statistics series no. 36, Cat no. PER 108.
- , IARC Working Group on the Evaluation of Carcinogenic Risks to Humans, International Agency for Research on Cancer.
- , City of Melbourne.
- , Quit Victoria.
- Greenhalgh E, Stillman S, Ford C 2020, ‘’, in Greenhalgh E, Scollo M, Winstanley M (eds) Tobacco in Australia: Facts and issues, Cancer Council Victoria.
- , 2019, Quit Victoria.