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Tobacco, Vaping, and Cannabis

Smoking and vaping exposures (second-hand and third-hand smoke and aerosol)

​​​​​​​​​​Second-hand exposure

When burned, cigarettes create tar, a sticky toxic chemical substance that clogs up the lungs. When someone smoking a cigarette exhales, the smoky air they breathe out combines with smoke from the burning cigarette to become second-hand smoke. There’s no known safe level of exposure to second-hand smoke from tobacco products.

Second-hand smoke exposure, including exposure at work or at home, can lead to serious health problems like:

  • heart disease
  • lower respiratory infections
  • asthma
  • lung cancer
  • sudden infant death syndrome (SIDS)

Children who live with second-hand smoke have higher risks of serious health issues like respiratory infections, multiple middle ear infections (that can lead to hearing loss), tonsillitis, childhood obesity, and breathing issues during sleep (like sleep apnea).

About 250 chemicals in tobacco cigarette smoke are harmful and at least 69 are known to cause cancer, including benzene. Benzene is also found in vaping products. You may have heard that some cigarette ingredients are approved as additives for foods we eat. This is true, but when they are burned or heated, they become toxic.

Cannabis smoke and aerosol are also health concerns. Cannabis smoke has some of the same harmful chemicals as tobacco smoke and can cause harm to the lungs. Although research is limited because of the recent legalization of cannabis, early evidence shows that children who live in homes with indoor cannabis smoking may have higher risks for health problems.

Aerosol is often seen when it is exhaled from the nose and mouth of people who vape. Aerosol may not be as harmful as second-hand smoke, but it does have some risk. Some of the chemical compounds in both e-liquids and aerosols are labelled as harmful, toxic, and cancer-causing. Nicotine, the addictive drug in tobacco products, is often found in vaping products. People who are exposed to second-hand aerosol have been found to have cancer-causing tobacco-specific nitrosamines in their urine, even if they don’t vape themselves.

Like second-hand smoke, second-hand aerosol can cause harm. To reduce your risk and your family’s risk, treat vaping exposure like smoking exposure.

Third-hand exposure

After the air clears from smoking or vaping, the toxic chemicals that settle on surfaces become a residue called third-hand smoke or third-hand aerosol.

Nicotine and other toxic chemicals have been found on surfaces like windows, walls, and floors in homes where people have either smoked or vaped. Being exposed to third-hand smoke may cause DNA damage and increase your risk of health problems, including asthma and cancer.

Residue has been found on windows, walls, and floors, as well as in dust and on wood and metal surfaces. Indoors, the residue can stay around for minutes to months.

Third-hand exposure can happen when you ingest (swallow) residue, breathe it in, or absorb it through your skin. Young children are especially vulnerable to third-hand exposure because of how they crawl, explore with their hands, and put their hands or toys in their mouths.

Reducing your risk

One way to reduce harm to you and your family’s health is to not allow smoke or aerosol inside your home and car. This is called making them “clean air spaces.” Everyone, including people who use tobacco or vaping products, will benefit from this healthy change. Even your pets will benefit.

In Alberta, it is illegal to smoke or vape in your vehicle with a child inside. Opening the window will not remove harm and may send smoke or aerosol into the back seat where children often sit.

Try these ideas to support a healthy smoke-free and aerosol-free environment:

  • Move all smoking and vaping outside of your home and your car. Moving smoking or vaping into another room, or where there is a window open, or in your heated garage will not stop the risk of second-hand or third-hand exposures. This is because smoke and aerosol spread out and your furnace circulates the air throughout your home.
  • Keep all outside use of tobacco and vaping products away from air intakes like doorways, open windows, and furnace and exhaust vents.
  • To remove third-hand smoke or aerosol residue from your home and car, consider washing down surfaces with soap and water, and cleaning your carpets and fabrics. You may prefer to paint your walls to cover up yellow smoke marks and to give your home a fresh look.
  • To reduce third-hand exposure to your family, wear a jacket when you smoke or vape outside and store the jacket away from other clothing. Wash your hands and face to remove residue on your skin. This is ​especially important to protect those you may cuddle or hold close.
  • Let family and friends know of your choice to go smoke-free and aerosol-free. Ask them to support your decision to reduce harm.

Support and information

Current as of: February 3, 2023

Author: Tobacco, Vaping, and Cannabis Program