Environmental pollutants and allergic rhinitis

Purpose of review: To review the current knowledge of the pathophysiology, epidemiology, and management of environmental pollutants and allergic rhinitis. Recent findings: Both active cigarette smoking and passive exposure to cigarette smoke are associated with chronic rhinitis and sinusitis. Matrix metalloproteinase 9, which is thought to contribute to the pathophysiology of allergy, is elevated in children with passive cigarette smoke exposure compared with controls. Ground-level ozone and particulate matter exposure is associated with an allergic-type response and may increase sensitization to other allergens. Certain occupational exposures can cause nasal irritation and local cytotoxic effects. Evidence suggests that rhinitis symptomatology may often precede the development of occupational asthma. Summary: Environmental factors have been noted to induce sinonasal mucosal irritation and often contribute to the multifactorial cause of chronic rhinitis and allergic rhinitis. Cigarette smoke is a common irritant that impacts the innate immune function of the sinonasal epithelial cells, and creates local irritation and cytotoxic effects. Both active smoking and exposure to second-hand smoke increase the risk of chronic rhinitis. Many other environmental pollutants are associated with chronic rhinitis, including ozone, particulate matter, and occupational irritants. The management of chronic rhinitis associated with environmental exposures is similar to the management of other types of chronic rhinitis. Although often not feasible, avoidance is probably the most effective course.