Our research has found that tiny nanoparticles, like those found in air pollution, can travel into the blood and accumulate in diseased blood vessels. The study suggests that air pollution nanoparticles are able to get into the bloodstream to cause heart disease.
The findings, published today in the journal ACS Nano, build on previous studies that have found tiny particles in air pollution are associated with an increased risk of cardiovascular disease, although the cause remains unproven.
However, this research shows for the first time that inhaled nanoparticles can gain access to the blood in healthy individuals and people at risk of stroke. Most worryingly, these nanoparticles tend to build-up in diseased blood vessels where they could worsen coronary heart disease – the cause of a heart attack.
Using gold nanoparticles
It is not currently possible to measure environmental nanoparticles in the blood. So, researchers from the University of Edinburgh, and the National Institute for Public Health and the Environment in the Netherlands, used a variety of specialist techniques to track the fate of harmless gold nanoparticles breathed in by volunteers.
They were able to show that these nanoparticles can migrate from the lungs and into the bloodstream within 24 hours after exposure and were still detectable in the blood three months later. By looking at surgically removed plaques from people at high risk of stroke they were also able to find that the nanoparticles accumulated in the fatty plaques that grow inside blood vessels and cause heart attacks and strokes.
Piecing together the evidence
Professor Jeremy Pearson, Associate Medical Director at the British Heart Foundation, which part-funded the study, said:
“There is no doubt that air pollution is a killer, and this study brings us a step closer to solving the mystery of how air pollution damages our cardiovascular health. More research is needed to pin down the mechanism and consolidate the evidence, but these results emphasise that we must do more to stop people dying needlessly from heart disease caused by air pollution.
“Crucially, individual avoidance of polluted areas is not a solution to the problem. Government must put forward bold measures to make all areas safe and protect the population from harm.”
Cardiovascular disease accounts for 80 per cent of all premature deaths from air pollution. Find out more about our research into air pollution, and how it can harm your health.
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