Passive smoking means breathing other people's second-hand tobacco smoke. Passive smoking is damaging because it increases risk of poor health including heart disease and cancer. People frequently exposed to second-hand tobacco smoke:

• are at 20-30% higher risk of lung cancer than people who are not exposed
• are exposed to more than 4,000 chemicals in the smoke - 69 are known to cause cancer
• are at high risk of premature death
• have a high risk of heart disease.

There is no known safe level for second-hand passive smoke. In children, passive smoking also causes lower respiratory illness and contributes to the symptoms of asthma.

Follow the links below to find trusted information about the health effects of passive smoking.