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  2. Indoor Air Quality (IAQ)

Secondhand Electronic-Cigarette Aerosol and Indoor Air Quality

On this page:

  • What is Secondhand Electronic-Cigarette Aerosol?
  • What are the Health Effects of Secondhand E-Cigarette Aerosol?
  • What Can I Do to Reduce Exposure to Secondhand E-Cigarette Aerosol?

Related pages:

  • Secondhand Smoke and Electronic-Cigarette Aerosols
  • Secondhand Tobacco Smoke and Indoor Air Quality
  • Secondhand Marijuana Smoke and Indoor Air Quality
  • Secondhand Smoke and Electronic-Cigarette Aerosol Resources

different types of e-cigarettes

What is Secondhand Electronic-Cigarette Aerosol?

Aerosols are a mix of tiny particles and/or droplets in the air. Electronic cigarettes produce an aerosol by heating a liquid that usually contains nicotine, flavorings and other chemicals.

E-cigarette users inhale this aerosol into their lungs. Bystanders can also breathe in this aerosol when the user exhales into the air.

These aerosols can contain potentially harmful substances — including nicotine, formaldehyde and metals — some of which cause cancer and other harmful health effects.

The amount, quantity and toxicity of substances that e-cigarettes release depend on several factors, such as the type of device, how the device operates and is used, and the e-liquid used.

Learn more about e-cigarette aerosol from the Centers for Disease Control and Prevention. 


 

What are the Health Effects of Secondhand E-Cigarette Aerosol?

Research indicates that e-cigarettes may emit harmful substances, which means there could be health risks to the user and others through secondhand exposure.

Some of the harmful substances emitted in secondhand e-cigarette aerosols are the same as those in secondhand tobacco smoke. However, more research is needed to fully understand emissions from e-cigarettes and their impact on human health. 


What Can I Do to Reduce Exposure to Secondhand E-Cigarette Aerosol?

Prohibiting e-cigarette use inside or near buildings, vehicles and other enclosed spaces is the only way to eliminate exposure to secondhand e-cigarette aerosol and health risks that may come with it.

Ventilation, filtration and air cleaning techniques may reduce harmful substances released from e-cigarette use indoors but are not likely to eliminate them. 

If you want to quit, resources are available.

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Last updated on May 13, 2025
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