Ozone in the Development of Pediatric Asthma and Atopic Disease

Abstract

Ozone (O₃) is a ubiquitous outdoor air pollutant, which may be derived from various primary pollutants such as nitrates, hydrocarbons, and volatile organ compounds through ultraviolet radiation exposure, and has been shown to negatively impact respiratory health. O₃ is the most common noninfectious environmental cause of asthma exacerbations among children and adults. Its effects on pediatric respiratory health could be due to multiple physiologic factors that may contribute to enhanced O₃ exposure seen in children compared with adults, including differences in lung surface area per unit of body weight and ventilation rates. O₃ can reach the distal regions of human lungs due to its low water solubility, resulting in either injury or activation of airway epithelial cells and macrophages. Multiple epidemiologic studies have highlighted a link between exposure to air pollution and the development of asthma. This review article specifically focuses on examining the impact of early life O₃ exposure on lung development, lung function, and the risk of developing atopic diseases including asthma, allergic rhinitis, and atopic dermatitis among children.

Keywords: Allergic rhinitis; Asthma; Atopic dermatitis; Children; Lung function; Ozone.

Fig. 1.

Ozone exposure and the development of asthma and atopic disease. (A). Ozone exposure during lung development causes morphologic and structural changes: decreases bronchial branching and alveoli number, alterations in smooth muscle bundle orientation, and hyperinnervation of pulmonary epithelium. (B). Ozone exposure during early life increases the risk of developing asthma, allergic rhinitis, and atopic dermatitis.