The goal of this study is to see how the type and size of particles found in air pollution affects inflammation in the nose in people who are skin test positive to at least one allergen. It has been observed that pollution makes allergies worse. It has also been suggested that very small particles may affect allergies more than larger particles.

Cough, bronchitis, asthma, and chronic obstructive pulmonary disease are all associated with elevated pollution particle levels. Researchers believe that particulate pollutants can exacerbate allergy and inflammation and affect asthma and allergy prevalence. In an urban setting such as the Los Angeles Basin, particles generated by vehicular traffic are thought to be important risk factors. Recently, the Environmental Health Centre of Southern California confirmed that there is a strong association between traffic near homes and schools and development of asthma. This study will help researchers describe the effects of various size pollution particles in causing inflammation in the nose.

There will be a total of 20 study visits. The study procedures include physical exams, symptom score for nose, nose washes and nose challenges with particulate matter. The particulates will be given in a random order and include the following: saline (sterile salt water), inert carbon particles (Carbon Black), diesel exhaust particles (DEP), small (fine) particles or very small (ultrafine) particles. These last two (fine and ultrafine) particles are obtained from concentrated normal Los Angeles air. The particulate will be sprayed into the nose with a standard nasal spray.

Inclusion Criteria:

• Previously determined high inflammatory responders to Diesel Exhaust Particles
• Previously determined atopy as demonstrated by allergy skin testing
• Asymptomatic on day of challenge.

Exclusion Criteria:

• History of lung problems (including asthma), bleeding, neuromuscular, liver, kidney or heart disorders.
• History of anaphylaxis.
• Recent upper respiratory infection (less than 4 weeks prior to study) or other active infection.
• Active smoker or smoker in the past 2 years.
• Treatment with topical nasal steroids (< 1 month), systemic steroids (<1 month), oral antihistamines (< 1 week) prior to any nasal challenge.
• Use of leukotriene receptor antagonist (< 1 month ) prior to any nasal challenge
• Intranasal antihistamine or cromolyn use < 1 week prior to any nasal challenge .
• History of treatment with allergy immunotherapy.
• Inability to perform nasal lavage.
• Inability to give written informed consent
• Pregnancy