An increase in the pollution level can increase the risk of several health issues. Exposure to ozone, a powerful greenhouse gas, may cause cardiovascular disease such as heart attack, high blood pressure and stroke, according to a new study of Chinese adults.
Ozone is a pollutant formed through a chemical reaction that occurs when sunlight interacts with nitrogen oxides and other organic compounds that are generated by coal-burning, vehicle exhaust and some natural sources.
Junfeng Zhang, from Duke and Duke Kunshan University and his colleagues, studied 89 healthy adults living in Changsha City of China for one year. They monitored 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 called spirometry to examine a set of factors that could contribute to cardiovascular and respiratory diseases. The team examined inflammation and oxidative stress, arterial stiffness, blood pressure, clotting factors and lung function in participants.
They noted blood platelet activation, which is a risk factor for clotting, and an increase in blood pressure, suggesting a possible mechanism by which ozone may affect cardiovascular health.
These effects were found with ozone exposure lower than that which affects respiratory health, and lower than current U.S. Environmental Protection Agency (EPA) air quality standards.
"This study shows that standards for safe ozone exposure should take into account its effect on cardiovascular disease risk," said Zhang. These findings, by a team from Duke University, Tsinghua University, Duke Kunshan University and Peking University, were published in the US journal JAMA Internal Medicine.
With Inputs From IANS