Don't sit next to the photocopier

The main trigger for a heart attack is not vigorous exercise or stress — it’s air pollution, according to a study published in The Lancet this month.

Researchers found spending time in traffic, whether as a driver or pedestrian, tops the list of ‘last straw’ risk factors that bring on a heart attack. Polluted air contains particles of dust and soot less than ten microns wide (one micron is a millionth of a metre) which get into the lungs and cause inflammation.

Jon Ayres, professor of environmental and respiratory medicine at the University of Birmingham, says: ‘Particles raise the risk of respiratory problems and also seem to increase the stickiness of the blood. So, if you’ve got coronary heart disease, it may contribute to causing a heart attack.’

Air pollution is not only linked to strokes, heart attacks and cancer — it has a profound effect on those with existing respiratory conditions. Asthmatics are more likely to have an asthma attack on days when pollution is high.

So how can you minimise the damage? We asked the experts for their tips on breathing easy.