Passive smoking - what is?

The 'side-stream' smoke that comes off a cigarette between puffs carries a higher risk than directly inhaled smoke.

Children who grow up in a home where one or both of their parents smoke have twice the risk of getting asthma and asthmatic bronchitis. They also have a higher risk of developing allergies.

Infants under two years old are more prone to severe respiratory infections and cot death.

For adults, passive smoking seems to increase the risk of lung cancer, but the evidence for an increased risk of heart disease is not yet conclusive.