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Science

Drugs and you

Tobacco

cigarette packets with warnings such as "Smoking kills" and "Smoking seriously harms you and others around you"

Warnings such as 'Smoking can cause a slow and painful death' are used to deter people from smoking

About 114,000 people die every year as a result of smoking-related illnesses. All cigarettes sold now carry a prominent health warning.

Cigarettes contain about 4,000 different chemicals, many of which are harmful to the body.

Nicotine is the addictive substance in tobacco smoke. It reaches the brain within 20 seconds and creates a dependency so that smokers become addicted.

Carbon monoxide

Carbon monoxide combines with the haemoglobinhaemoglobin: The red protein found in red blood cells that transports oxygen round the body in red blood cells and so reduces the ability of the blood to carry oxygen. This puts extra strain on the circulatory system, and can cause an increased risk of heart disease and strokes.

Smoking during pregnancy is very dangerous. It reduces the amount of oxygen available to the growing fetus. This leads to an increased risk of

  • miscarriage and premature birth
  • low weight of babies at birth

Carcinogens

Carcinogens are substances that cause cancer. Tobacco smoke contains many carcinogens, including tar. Smoking increases the risk of lung cancer, mouth cancer and throat cancer.

The images below compare a healthy lung and a smoker's lung. You can see the tar deposits in the smoker's lung.

the lung is pink

A healthy lung

the lung is tinged yellow and has black tar deposits

A smoker's lung, with tar deposits visible

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