Ozone & Oxidants

This report describes a study by Dr. Last to investigate possible synergistic effects of multiple air pollutants on pulmonary measures in rats. Rats were exposed for 1-9 days to mixtures of O₃ or NO₂ and aerosols of sulfuric acid, ammonium sulfate, or sodium chloride, and to each pollutant individually. Responses were evaluated by various biochemical and morphometric analyses of lung tissue and lavage fluid. An additional preliminary experiment treated exposed rats in vivo with various free-radical scavengers to elucidate possible protective properties.

This report investigated whether asthmatic and healthy adolescents differ in their sensitivity to near-ambient concentrations of ozone and nitrogen dioxide. Dr. Koenig and colleagues exposed healthy and asthmatic participants to concentrations of 0.12 and 0.18 ppm ozone or 0.12 and 0.18 ppm nitrogen dioxide during rest or rest followed by moderate exercise.

Dr. Drechsler-Parks and colleagues at the Institute of Environmental Stress sought to examine the effects of nitrogen dioxide, ozone, and peroxyacetyl nitrate on metabolic and pulmonary function. Because it is possible that two or more pollutants could interact in ambient air and cause effects that could not be predicted from the effects observed with the individual pollutants, the investigators examined varying levels of different pollutants in 32 non-smoking men and women (8 men and 8 women 18-26 years of age and 8 men and 8 women 51-76 years of age).