The fact that vitamin C didn't block the blood pressure response suggests that it's likely caused by a sudden increase in sympathetic nervous system activity.
The findings confirm that PM, not ozone, is responsible for the rapid increase in diastolic blood pressure and that this occurs only during actual inhalation of PM. The research also confirms that PM impairs blood vessel function one day after exposure. However, this blood vessel function response occurred only in Toronto, which suggests that the composition of PM or its source may play a role in determining that kind of response, the researchers said.
The study was expected to be presented Wednesday at the American Society of Hypertension annual meeting, in New Orleans.
"These findings are a springboard for further study that will specifically determine how the sympathetic nervous system responds and to what types of particles in air pollution," Brook said. "But this glimpse helps us determine the triggers behind a range of CV events -- some deadly. Learning how this dangerous cascade starts can help the medical and public health community make advances toward limiting their impact in the future."
More information
The American Academy of Family Physicians has more about air pollution and health.
