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Smoking & tobacco

Second–hand smoke

Second-hand smoke is a complex mix of chemicals produced by burning tobacco. Just like primary smoking, second-hand smoke can cause disease and death.

What is second-hand smoke?
Second-hand smoke is made up of the smoke from the burning end of a cigarette or pipe, and the smoke that is blown into the air by the person smoking.

Second-hand smoke has over 4,000 chemicals; many of them cause cancer. Two thirds of the smoke from a cigarette is not inhaled by the smoker, but enters the air around the smoker.

  • Second-hand smoke has at least twice the amount of nicotine and tar as the smoke inhaled by the smoker
  • It has five times the amount of carbon monoxide, a deadly gas that robs the blood of oxygen
  • It also contains higher levels of ammonia (better known as window cleaner) and cadmium (also found in batteries)
  • The concentration of hydrogen cyanide (a poisonous gas that attacks respiratory enzymes) in tobacco smoke is considered toxic
  • It contains nitrogen dioxide which is measured at fifty times higher than the standard for harm
  • Non-smokers who breathe in second-hand smoke can get many serious diseases. It can cause lung cancer, heart disease, Chronic Obstructive Pulmonary Disease (emphysema and chronic bronchitis) asthma and other diseases
  • Regular exposure to second-hand smoke increases the risk of lung disease by 25% and heart disease by 10%

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