Toxic air significantly increasing city residents’ risk of heart disease

City residents’ hearts could be up to ten times more polluted than those living in places with cleaner air, significantly increasing their risk of heart disease, a study has found.

A global team of academics analysed the hearts of 72 people aged between three and 32. Sixty-three of these were taken from the victims of traffic accidents in the heavily polluted Mexico City which were compared with nine hearts from people who had lived in cleaner areas.

They found that the hearts belonging to Mexico City residents contained much higher numbers of iron-rich magnetic nanoparticles created from pollution from traffic and industry.

When a human heart is exposed to these nanoparticles, it can inflame heart tissues causing damage which could potentially lead to serious problems such as heart disease or heart failure.

They also found these nanoparticles in many different cell structures in the left ventricle of the heart, even in the mitochondria — which is crucial for supplying the energy needed for the heart to pump effectively.

Prior to this study, little was known about the abundance of these metal-rich and magnetic nanoparticles in human heart tissue or what specific damage they could be causing, even in children and young adults.

The researchers say their findings provide a new way of understanding heart disease risks and underline the importance of ‘urgent action’ on particulate air pollution controls to protect human health.

Professor Barbara Maher from the University of Lancaster co-led the study. She said: ‘Exposure to this type of metal-rich nanoparticle appears to be directly associated with early and significant inflammation and cardiac damage.

‘Identification of billions of strongly magnetic nanoparticles in the hearts of children and young adults provides an important new layer of information for understanding the development of cardiovascular disease.’

Professor Lilian Calderon Garciduenas from the University of Montana added: ‘Exposure to iron-rich, combustion- and friction-derived nanoparticles is a modifiable risk factor for the development of cardiovascular diseases and this new evidence highlights the need for urgent progress in global efforts to reduce exposure to particulate matter air pollution and, specifically, to reduce and regulate the nanoparticles in air pollution.’

Read the paper here.

In June, a study found that long-term exposure to ambient ozone (O3) in the air may speed up the development of heart disease such as atherosclerosis.