Secondhand smoke and you

What is Secondhand Smoke (SHS)?

Secondhand smoke, also known as environmental tobacco smoke (ETS), is a mixture of the smoke exhaled by smokers (mainstream smoke) and the smoke given off by the burning end of tobacco products (sidestream smoke).

The Harmful Effect of SHS

Studies show that secondhand smoke, similar to active smoking, can cause many fatal diseases such as heart diseases and cancers. Secondhand smoke contains a complex mixture of more than 7000 chemicals (e.g. cyanide, arsenic), of which at least 69 carcinogens (e.g. nitrosamine, aldehyde, chromium). The concentrations of some toxins contained in sidestream smoke such as carbon monoxide, ammonia, benzene, hydrocarbon compounds etc, were found to be higher than mainstream smoke. In 1992, secondhand smoke was classified by the US Environmental Protection Agency (EPA) as "Group A carcinogen" and there is no risk-free level of exposure for secondhand smoke.

The acute effects of secondhand smoke to human include eye irritation, sore throat and cough.  However, in the long run, studies show that secondhand smoke can cause or associate with the following fatal diseases:

  1. Cancers - lung cancer, nasal sinus cancer and breast cancer (pre-menopausal young women)

  2. Cardiovascular diseases - a local study shows that the risk of a non-smoker who died from stroke increases if the number of smokers who lived or worked with that non-smoker increases. Secondhand smoke causes injuries to blood-vessels and disrupts the normal functioning of blood clotting mechanisms.

  3. Respiratory diseases - asthma, otitis media (middle ear infection), lower respiratory tract infections and symptoms of respiratory tract irritation

  4. Complications of pregnancy and foetal development - miscarriage, low birth weight and Sudden Infant Death Syndrome (SIDS)

For further information about the effect of secondhand smoke on health, please visit:

Centers for Disease Control and Prevention, USA
National Cancer Institute, USA
Office of Environmental Health Hazard Assessment, California, USA
World Health Organization
Department of Health, UK

If you need any assistance or information on smoking cessation, please contact us at 1833183.