Oxidant and Acid Aerosol Exposure in Healthy Subjects and Subjects with Asthma.Part 1. Effects of Oxidants, Combined with Sulfuric or Nitric Acid, on the Pulmonary Function of Adolescents with Asthma. Part 2. Effects of Sequential Sulfuric Acid and Ozone

摘要

The study investigated the pulmonary effects of acid summer haze in a controlledlaboratory setting. Of 28 adolescent subjects with allergic asthma, exercise-induced bronchospasm, and a positive response to a standardized methacholine challenge enrolled in the study, 22 completed the study. For two consecutive days each subject inhaled each of four test atmospheres by mouthpiece. The order of exposure to the four test atmospheres was assigned via a random protocol; air, oxidants (0.12 parts per million (ppm) ozone plus 0.30 ppm nitrogen dioxide), oxidants plus sulfuric acid at 70 micro/m3 of air, or oxidants plus 0.05 ppm nitric acid. Exposure to each of the different atmospheres was separated by at least one week. A postexposure methacholine challenge was performed on Day 3.