I'm READY to QUIT smoking

Start your quit smoking journey with us today!

Join iCanQuit now

Passive Smoking (Second-Hand Smoke)

What is Passive Smoking?

Passive smoking is when someone breathes in the combination of:

Smoke exhaled by a smoker + Smoke from the end of a burning cigarette or cigar

This smoke is also referred to as second-hand smoke or environmental tobacco smoke.

The Effects of Passive Smoking

The scientific evidence about passive smoking shows us just how dangerous second-hand smoke really is.

Here are the facts about passive smoking:

  • Non-smokers exposed to second-hand smoke have an increased risk of lung cancer
  • Non-smokers who live with a smoker are 20-30% more likely to develop lung cancer
  • Passive smoking can cause premature death in non-smokers
  • Passive smoking increases the risk of coronary heart disease by 25-40% - almost the same level as a smoker
  • Second-hand smoke contains more than 7000 chemicals, with 69 cancer-causing chemicals
  • There is no known safe level of exposure to second-hand smoke

Did you know that your health can start improving as soon as you quit smoking? Click here to discover the health benefits of quitting.

Why is passive smoking so dangerous?

But how can passive smoking be so damaging? After all, a non-smoker doesn’t breathe in anywhere near as much tobacco smoke as a smoker.

The answer lies in the smoke that comes from a cigarette once it’s burnt, with some evidence showing that:

  • Smoke that burns off the end of a cigarette �� called sidestream smoke – may be even more toxic than the smoke inhaled by a smoker
  • Sidestream smoke may get more toxic as it goes from fresh to stale
  • Low doses of tobacco are all that’s needed to trigger off a series of events that can lead to heart disease
  • Some research shows that the effect of exposure for a few minutes to a few hours can be just as dangerous as chronic smoking on the heart 
  • This tells us that breathing in second-hand cigarette smoke carries serious health risks, with no known safe level of exposure to passive smoking

What can I do about second-hand smoke while I’m still smoking?

If you're not ready to quit smoking, think about how you can reduce some of the impact of your smoking on those around you.


  • Smoke moves around in the air where others can breathe it in. 
  • The effects of second-hand smoke are significant – it’s not just the amount of smoke, but the type of smoke and how it triggers damaging processes in the body, even at low levels.

Here are some quick tips for reducing the impact of smoking on others:

  • Don’t smoke in the home to reduce the health consequences of passive smoking on your family.
  • Try wearing a ‘smoking jacket’ – that way, you can take the item off before you enter your home, or perhaps have a shower and change your clothes.
  • Plan your quit smoking journey. Of course, the most effective way to protect those around you from your smoking is to make quitting a priority! Why not start today


Smoking affects more people than just the smoker. Reduce the health risks of passive smoking for your family by making your home and car ‘smoke-free zones’.

My Quit Plan features handy online tools to help you track your quit smoking progress – check it out! >

I’m ready to stop smoking Join iCanQuit now it’s free!