Researchers have proved for the first time that toxic particles from diesel vehicles can make their way through the lungs and into the blood stream, this greatly increases the chances of someone having a heart attack or stroke.
The nanoparticles can stay in the body for months and can build up in areas which are prone to disease.
A team at Edinburgh University used harmless gold nanoparticles in a human experiment, this simulated cycling through the city.
After looking at surgically removed samples the researchers found that the gold had managed to accumulate in the fatty areas inside blood vessels that are responsible for a heart attack or stroke.
Dr Nicholas Mills, Professor of Cardiology at Edinburgh and one of the study’s co-authors, said: “We have always suspected that nanoparticles in the air that we breath could escape from the lung and enter the body, but until now there was no proof.
“These findings are of wide importance for human health, and we must now focus our attention on reducing emissions and exposure to airborne nanoparticles.”