Effects of air pollutants on upper airway disease

Purpose of reviewWe discuss the effects of air pollutants on upper airway disease; the topic has hitherto received little attention.Recent findingsSeveral epidemiological studies have shown that air pollutants aggravate airway diseases including asthma, bronchitis, and chronic obstructive pulmonary disorder. Pollutants also have negative effects on other upper airway diseases such as allergic and nonallergic rhinitis, sinusitis, and otitis media. Traffic-related air pollutants (diesel exhaust particles and nitrogen dioxide and tobacco smoke) have been widely studied in this context. Increasing evidence suggests that particulate matter, photochemical pollutants, and ozone are associated with such conditions. Young children and the obese are more vulnerable. Work in vivo and in vitro has explored the relationships between pollutants and disease, and possible pathophysiological mechanisms. Reactive oxygen species, apoptosis, and inflammation are all in play.SummaryTraffic-derived materials and tobacco smoke are major air pollutants that aggravate upper airway disease. Novel mechanisms of action have been suggested and risk factors have been defined. However, the data are conflicting, and controlled prospective studies are required.