* Secondhand smoke exposure causes heart disease and lung cancer in nonsmoking adults.2 * Nonsmokers who are exposed to secondhand smoke at home or work increase their heart disease risk by 25--30% and their lung cancer risk by 20--30%.2 * Breathing secondhand smoke has immediate harmful effects on the cardiovascular system that can increase the risk of heart attack. People who already have heart disease are at especially high risk.2 * Secondhand smoke exposure causes respiratory symptoms in children and slows their lung growth.2 * Secondhand smoke causes sudden infant death syndrome (SIDS), acute respiratory infections, ear problems, and more frequent and severe asthma attacks in children.2 * There is no risk-free level of secondhand smoke exposure. Even brief exposure can be dangerous.2