This study is designed to investigate whether exposure to particulate air pollution
increases the allergic response to allergens. Research studies suggest that symptoms in
individuals with allergies may be aggravated by exposure to particulate air pollution. We
sought to experimental determine this by exposing human volunteers to combustion particles,
a component of air pollution, and then challenge them with an allergen such as ragweed or
oak tree pollen. Using biological tests we can measure whether the allergen response is
magnified by prior particulate exposure.
To study whether particulates enhance the allergic response, we chose the upper airway as a
model of allergic inflammation and nasal lavage as a non-invasive method for obtaining
samples. The nasal cavity is both an excellent model of allergic inflammation and provides
an easily accessible site for study. We measured inflammatory cells and cytokines in the
nasal lavage fluid. Our specific hypothesis was that particulate exposure prior to allergen
challenge would enhance inflammatory cell recruitment and expression of inflammatory
Adult without a history of asthma or respiratory disease.