A recent study by EPA and the University of North Carolina researchers claims that exposure of healthy young adults to low levels of ambient ozone may lead to decreased lung function and airway inflammation. Chong Kim, et al., “Lung Function and Inflammatory Responses in Healthy Young Adults Exposed to 0.06 ppm Ozone for 6.6 Hours,” American Journal of Respiratory and Critical Care Medicine, January 7, 2011. The researchers exposed 59 healthy adults between the ages of 19 and 35 to ozone concentrations of 0.06 parts per million (ppm) for 6.6 hours while undergoing moderate exercise.

The study found that the exposure resulted in reduced lung function by 1.75 percent and a 15-percent increase in pulmonary inflammation. EPA’s current national ambient air quality standard (NAAQS) for ozone is 0.075 ppm, averaged over eight hours. EPA has proposed setting a health-based standard for ozone in a range between 0.060 and 0.070 ppm, averaged over eight hours. The proposed rule should be finalized in July 2011, according to the agency. See BNA Daily Environment Report, January 11, 2011.