How does pollution worsen allergies?

There is increasing evidence that pollution contributes to the rise in allergic diseases.1-3 Major pollutant contributors to this trend include particulate matter (PM), greenhouse and other harmful gases, and pollen.1-9 The studies conducted by various research groups have advanced our understanding of mechanisms by which pollution worsens allergies. The PM, in particular, is a complex mixture of components, and exposure to PM has been reported to worsen preexisting allergic disease symptoms.1,3,4 Furthermore, PM2.5, particles with a diameter of less than 2.5 mm, is considered the most harmful because of its ability to travel deep into the bronchioles and alveoli of the lungs.
Source: Annals of Allergy, Asthma and Immunology - Category: Allergy & Immunology Authors: Tags: Editorial Source Type: research