Children have a higher breathing rate than adults relative to their body weight and lung surface area. This results in a greater dose of pollution delivered to their lungs. Most biological air pollution damage is related to the dose of pollution inhaled in relation to the body weight and surface area of the target organ. Even when children experience significant drops in lung function, they do not seem to suffer or report some of the acute symptoms, such as coughing, wheezing or shortness of breath, associated with ozone exposure in adults. Thus, children are not likely to receive or may not understand the biological warnings to reduce their ozone exposure by stopping their exercise or moving indoors.
Children have narrower airways than do adults.
Thus, irritation or inflammation caused by air pollution that would produce only a slight response in an adult can result in a potentially significant obstruction of the airways in a young child. During exercise, children, like adults, breathe with both their nose and mouth rather than just their noses. When the nose is bypassed during the breathing process, the filtering effects of the nose are lost, therefore allowing more air pollution to be inhaled. Air pollution, including ozone, can result in more frequent respiratory infections in children due to impairment of the lung's ability to defend itself. When ozone levels are high, children should avoid calisthenics, soccer, running and other strenuous outdoor exercise.