Physiological changes in healthy volunteers from ozone exposure mirror cardiovascular ailments
MONDAY, June 25 (HealthDay News) -- Ozone exposure in healthy young adults causes an increase in vascular markers of inflammation, changes in fibrinolytic markers that could potentially impair fibrinolysis, and changes in autonomic control of heart rate, according to a study published online June 25 in Circulation.
Robert B. Devlin, Ph.D., from the U.S. Environmental Protection Agency in Research Triangle Park, N.C., and colleagues exposed 23 young healthy individuals to clean air and to 0.3-ppm ozone for two hours during intermittent exercising. Before exposure, immediately after exposure, and the next morning, blood was obtained. Participants used a continuous Holter monitor immediately after exposure for a 24-hour period. Additionally, lung function was performed immediately before and immediately after exposure, and bronchoalveolar lavage was performed 24 hours after exposure.
The researchers found a 98.9 percent increase in interleukin-8, a 21.4 percent decrease in plasminogen activator inhibitor-1, a 51.3 percent decrease in the high-frequency component of heart rate variability, and a 1.2 percent increase in QT duration, immediately after ozone exposure. Twenty-four hours after exposure, changes in interleukin-1B and plasminogen activator inhibitor-1 were apparent. Participants also had ozone-induced drops in lung function and an increase in pulmonary inflammation.
"This study provides a plausible explanation for the link between acute ozone exposure and death," Devlin said in a statement.