Air pollution is both a known risk factor for asthma AND an everyday irritant for kids and adults who have asthma already. Now a new study, supported by the U.S. National Institutes of Health and Environmental Protection Agency, suggests that even when air pollution levels fall within what are considered acceptable air quality standards, inner-city kids who have asthma continue to suffer.

The Inner City Asthma Study Group monitored the asthma symptoms of kids who lived in low-income, inner-city sections of Boston, New York City, Chicago, Dallas, Seattle and Tucson for more than 2 years. Here are the highlights of the study:

• Study looked at 861 children, ages 5 to 12, with persistent asthma
• Kids had significantly decreased lung function after being exposed to common air pollutants such as sulfur dioxide, airborne fine particles, and nitrogen dioxide
• Higher nitrogen dioxide levels and higher levels of fine particles were associated with asthma-related school absences
• Motor vehicle exhaust is the main source of nitrogen dioxide

The researchers suggest that asthma management plans for inner-city kids need to focus on reducing exposure to air pollutants. They also questioned whether their findings raise questions about current air quality standards in the United States. Air quality is an important factor in most respiratory illnesses, including asthma.