Breathing Polluted Air Raises Blood Pressure

Sanjay Rajagopalan, M.D.
Division of Cardiovascular Medicine
Ohio State University Medical Center
NIEHS Grants R01ES015146, R01ES013406, and P30ES000260

A new study by cardiovascular researchers at the Ohio State University Medical Center is the first to report a direct link between air pollution and high blood pressure. The study, performed in laboratory animals, could have important implications for human health.

The research team exposed rats to levels of airborne pollutants that humans breathe on a regular basis. The levels were much lower than those seen in developing areas of China and India and some regions of the US. They found that short term exposure to these pollutants, over a 10-week period, elevated blood pressure in rats that were predisposed to the condition. These results are consistent with human observational studies that demonstrate similar blood pressure increases within hours to days following exposure.

Rats were exposed to concentrations of particulate matter air pollution comparable to levels seen in US cities with heavy commuter traffic. When rats were given angiotensin II a naturally occurring hormone involved in blood pressure regulation, and exposed to particulate pollution, their blood pressure rose sharply as compared to rats that breathed filtered air.

A continuation of this work is being conducted in Beijing in association with the Summer Olympics. The researchers will measure vascular function in people before and after stringent air quality improvements are made for the games. They expect to find tangible impacts on vascular function and blood pressure.

Citation: Sun Q, Yue P, Ying Z, Cardounel AJ, Brook RD, Devlin R, Hwang JS, Zweier JL, Chen LC, Rajagopalan S. Air Pollution Exposure Potentiates Hypertension Through Reactive Oxygen Species-Mediated Activation of Rho/ROCK. Arterioscler Thromb Vasc Biol. 2008 Jul 3.