The respiratory effects of passive tobacco smoking.

Smokers not only increase their own risk of pulmonary disease, but contribute to the health risk of nonsmokers through the production of environmental tobacco smoke. Evidence continues to build regarding the positive association between passive smoking and increased risk of respiratory symptoms and lung diseases. Environmental tobacco smoke exposure has been implicated in both the development and worsening of airway hyperresponsiveness and wheezing. Pulmonary function reduction has been documented in children with both prenatal and postnatal exposure, but the presence of increased airway obstruction and its long-term significance is unclear in adults. There is growing concern about the risk of lung cancer, particularly among female never-smokers exposed to tobacco smoke in the home and workplace. Environmental tobacco smoke is a major component of indoor air pollution and a major public health threat. Most importantly, it is a preventable risk and efforts to control and eliminate exposure need to be encouraged.