Air Pollution Aggravates Allergies
A recent review of the effect of air pollution on allergies concludes that “the body of current scientific data now clearly delineates the role of pollutant-mediated adverse interactions in human allergic airway diseases. The allergist-clinical immunologist should be keenly aware that both gaseous and particulate outdoor pollutants might aggravate or enhance the underlying pathophysiology of both the upper and lower airways.”
This review article summarizes recent advances in animal toxicology, epidemiology, human exposure, and tissue and cellular studies in identifying the effects of diesel exhaust particulate matter, sulfur dioxide, nitrogen dioxide and ozone on the aggravation of asthma and allergies. It reviews potential mechanisms and discusses interactions between allergens and pollutants.
It reports, for instance, that ozone has been associated with increased risk of asthma development among children in California playing outdoor sports and that ozone can increase airway inflammation and airway responsiveness and potentiate the airway response to inhaled allergens. Nitrogen oxides are linked to an increase in respiratory infection and wheezing and can increase the effects of inhaled allergen responses. In high concentrations, sulfur dioxide with or without exercise, is a respiratory irritant, provoking airflow limitations. Diesel exhaust particulates increase airway inflammation and can exacerbate and initiate asthma and allergies.
“As patient advocates, physicians, both individually and as members of large health organizations, should support societal control of air pollution and rally against attempts to weaken science-based regulatory air pollution standards,” conclude the authors.
Bernstein JA, Alexis N, Barnes C, Bernstein IL, Nel A, Peden D, Diaz-Sanchez D, Tarlo SM, Williams PB. Health effects of air pollution. J Allergy Clin Immunol 2004; 114:1116-23.
The National Library of Medicine [www.ncbi.nlm.nih.gov] offers the abstract online.
