Secondhand Smoke

What is Second Hand Smoke?

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Also known as involuntary or passive smoking, second-hand smoking results in a number of harmful chemicals being shared with friends, strangers, family and even the pets of smokers.

What is second-hand smoke?

The vapours inhaled from a burning cigarette are called ‘first-hand’ or ‘mainstream’ smoke. At the same time as a smoker smokes, people around them are exposed to what’s called ‘sidestream’ smoke. The combination of sidestream smoke and any exhaled smoke in the air is called second-hand smoke.

This smoke contains the same combination of over 7,000 chemicals that smokers inhale themselves, including many that are harmful.1

Studies show that non-smokers who live with smokers have a 25-30% greater risk of developing coronary heart disease, than people living in a smoke-free environment.3

What’s bad about second-hand smoking?

The proportions of chemicals produced by first-hand smoking vary when compared with second-hand smoke, but the chemicals themselves are generally the same. Some examples of toxic chemicals are:

  • Carbon monoxide, which inhibits the ability of the lungs to take up oxygen.4
  • Nicotine, which provides the short-lived feelings that get smokers hooked.6
  • Tar, which can coat the lungs4

How does second-hand smoking affect children?3

Second-hand smoke statistics make difficult reading.

  • There is no safe level of exposure to second-hand smoke.3
  • Children can suffer from a range of upper and lower respiratory illnesses when exposed to second-hand smoke.5 
  • A young person regularly exposed to second-hand smoke has a 20%-30% increased risk of developing lung cancer than those brought-up in a smoke-free environment.3

What about pregnant women and their babies?

Studies suggest that the risk of miscarriage and premature birth increases if a mother smokes during pregnancy, as does the likelihood of low birth weight. Health problems such as respiratory infections, asthma and allergies are more common in the infants of smokers.5