The team studied 19 people with diabetes, measuring how their bodies adjusted to breathing in either highly purified air or air that included ultrafine particles.
Scientists found that after exposure to the particles, participants had higher levels of two well known markers of cardiovascular risk, activated platelets and von Willebrand factor. Both play a major role in the series of events that lead to heart attacks. Platelets, for instance, can stick to fatty buildups or plaques within the blood vessels and cause a clot, blocking blood flow to heart muscle.
"Platelets are the critical actor at the actual moment of a heart attack," said Frampton. "When a plaque ruptures, platelets glom onto it, forming a large clot. Normally, of course, platelets do not block blood flow and aren't a problem. Our findings indicate that when someone is exposed to air pollution, the platelets become activated, which would make them more likely to trigger a heart attack."
The particles used in the study were relatively "clean" ultrafine particles, made of pure carbon. Scientists have done other studies looking at the effects of ultrafine particles in people, but those studies usually have included other materials, such as gases and other particles, and have often been done with higher concentrations. Frampton and Stewart studied a concentration of particles that was 50 micrograms per cubic meter, which is lower than most studies though still higher than what most people are normally exposed to while breathing everyd
|Contact: Tom Rickey|
University of Rochester Medical Center