Cardiovascular researchers, led by an Indian-origin researcher, at The Ohio State University Medical Center have found a direct link between air pollution and its impact on high blood pressure, or hypertension.
"We now have even more compelling evidence of the strong relationship between air pollution and cardiovascular disease," said Sanjay Rajagopalan, section director of vascular medicine at Ohio State's Medical Center and co-author of the study.
To reach the conclusion, the research team exposed rats to levels of airborne pollutants that humans breathe everyday, noting the levels were still considerably below levels found in developing countries such as China and India, and in some parts of the U.S.
From the analysis, the researchers found that short-term exposure to air pollution, over a 10-week period, elevates blood pressure in those already predisposed to the condition.
The results appear online and are scheduled for publication in an upcoming issue of Arteriosclerosis, Thrombosis, and Vascular Biology, a journal published by the American Heart Association.
"Recent observational studies in humans suggest that within hours to days following exposure, blood pressure increases," said Rajagopalan.
In a highly-controlled experiment, hypertensive rats were placed in chambers and exposed to either particulate matter or filtered air for six hours a day, five days a week, over a period of 10 weeks.
At week nine, researchers infused angiotensin II, another pollutant, into mini-pumps within the chambers and monitored responses in blood pressure over one week.
The air pollution level inside the chamber containing particulate matter was comparable to levels a commuter may be exposed to in urban areas with heavy traffic such as downtown Manhattan.