Junfeng Zhang, Ph.D.
A new study, funded in part by NIEHS, revealed a link between exposure to ozone and health changes that may lead to cardiovascular disease. Adverse cardiovascular effects were observed with ozone levels lower than those known to affect respiratory health and levels lower than current U.S. Environmental Protection Agency (EPA) air quality standards.
For 2 months, researchers studied 89 healthy adults who lived on a work campus in China. They measured indoor and outdoor ozone levels, along with other pollutants. At four intervals, the study team took participant blood and urine samples and used a breathing test to examine inflammation and oxidative stress, arterial stiffness, blood pressure, clotting factors, and lung function in participants.
At ozone concentrations lower than levels known to influence pulmonary function, researchers found an association between increased ozone levels and blood platelet activation, which is a risk factor for clotting, as well as increased blood pressure. Both blood platelet activation and blood pressure are associated with increased risk for many cardiovascular diseases.
The findings revealed possible mechanisms by which ozone might affect cardiovascular health. According to the authors, the standard for safe ozone exposure should consider its association with cardiovascular disease risk, which may occur at lower levels of ozone than respiratory effects.
Citation: Day DB, Xiang J, Mo J, Li F, Chung M, Gong J, Weschler CJ, Ohman-Strickland PA, Sundell J, Weng W, Zhang Y, Zhang JJ. 2017. Association of ozone exposure with cardiorespiratory pathophysiologic mechanisms in healthy adults. JAMA Intern Med 177(9):1344-1353.