Air pollution can have short- and long-term health effects. Asthma from air pollution can have short- and long-term effects. Short-term effects of asthma are irritation to the eyes, nose, and throat. Long-term reactions to air pollution can include upper respiratory infections such as bronchitis and pneumonia. Other symptoms of exposure to air pollution are headaches, nausea, and allergic reactions. Short-term air pollution can aggravate underlying medical conditions of individuals with asthma and emphysema. Long-term health effects are more controversial. Depending on the type of air pollution, there is general consensus that exposure can cause chronic respiratory disease, lung cancer, heart disease, and damage to the brain, nerves, liver, or kidneys. Continual exposure to most kinds of air pollution affects the lungs of growing children by scarring them at early stages of development. Recent studies suggest that the closer one is raised to a freeway in southern California, a notoriously low-quality air region overall, the greater the chance of having one of the listed long-term effects.