Apples for Health- Ozone exposure bad for healthy young lungs

Ozone exposure bad for healthy young lungs

DAVIS, Calif., July 24 (UPI) -- The elderly are warned to avoid outdoors during high ozone levels but ozone has a negative effect on lung function in healthy adults, U.S. researchers said.
Researchers at the University of California, Davis, recruited 31 healthy non-smoking people to participate in 6.6-hour sessions during which they were exposed to ozone at 60, 70, 80 or 87 parts per billion, or filtered air, while undergoing six 50-minute bouts of moderate exercise followed by 10-minute breaks. A 35-minute lunch break separated the third and fourth bouts of exercise.
Lung function for each subject was assessed before, during and after exposure, and each individual answered a questionnaire evaluating subjective symptoms.
"The National Ambient Air Quality Standard for ozone was recently revised to set lower limits for ozone concentrations. Our research indicates that the threshold for decrements in ozone-induced lung function in healthy young subjects is below this standard," Edward Schelegle said in a statement. "Specifically, we found that 6.6 hours exposure to mean ozone concentrations as low as 70 parts per billion have a significant negative effect on lung function, even though the current NAAQS standards allow ozone concentrations to be up to 75 parts per billion over an eight-hour period."
The study is published in the American Journal of Respiratory and Critical Care Medicine.