Nonsmokers, who are generally more sensitive to the toxic effects of tobacco smoke than smokers, may experience headaches, sore throat, nausea, and dizziness. Second-hand smoke places extra stress on the heart and affects the body's ability to take in and use oxygen. Second-hand smoke increases the risk of death from heart disease by 20 to 30 per cent for nonsmokers married to smokers. 1 Second-hand smoke is the third largest cause of lung cancer, after direct smoking and occupational exposure to other hazardous substances. Up to one-quarter of lung cancer deaths in nonsmokers are related to secondhand smoke.
Children are especially sensitive to the effects of second-hand smoke.
3 Young children exposed to second-hand smoke are more vulnerable to respiratory illnesses such as bronchitis, asthma, and ear infections. Young children whose parents smoke at home suffer from twice as many respiratory illnesses and infections, such as colds, bronchitis, and pneumonia, as those who have non-smoking parents. Middle ear infections are also more common in the young children of smoking parents. 5 Second-hand smoke can trigger asthma attacks in children and is a risk factor for new cases of asthma. Approximately 300,000 Canadian children and adolescents have asthma.