Below is a summary of the recent scientific information regarding the health effects of these air pollutants. Ozone Ozone is the principle component of ground-level smog. It is formed when hydrocarbon and nitrogen oxide pollution from vehicles, power plants, refineries and other sources combine in the atmosphere in the presence of sunlight.
Ozone is a powerful oxidizing agent that damages lung tissue.
Recent research with laboratory animals, clinical subjects, and human populations has identified a cascade of adverse health effects from ozone at levels common in the United States. Effects include increased respiratory symptoms, damage to cells of the respiratory tract, declines in lung function, increased susceptibility to respiratory infections, and increased risk of hospitalization and early death. Short-term exposures to ozone can cause a decline in lung function, including rapid breathing, decreased lung volumes and flow, and increased twitchiness of the airways. Exposure early in life may lead to acceleration in the decline of lung function that is a normal process of aging. Respiratory symptoms can include coughing, throat irritation, shortness of breath, and pain on taking a deep breath.