Living for one year in an area with high levels of fine particulate matter (PM2.5) is as bad for human health as smoking 150 cigarettes a year, according to the British Heart Foundation.

To come up with the figure, the charity first estimated the average annual levels of PM2.5 exposure for the whole UK population (8μg/m3) and then equated breathing this density of PM2.5 directly to the equivalent number of cigarettes.

They scaled the number up to figure out how much daily exposure to PM2.5 is equal to smoking one daily cigarette, which they believe is around 28.8 8μg/m3.

So if you were to stay in a polluted area which had an average PM2.5 of 28.8μg/m3 for that day, it would have the equivalent effect on your health as staying in an area with no pollution and smoking one cigarette.

Average daily PM2.5 in the ten worst-polluted local authorities, which are all in the Greater London area, is 12.2μg/m3, which would equate to smoking 155 cigarettes per year.

In October, London Mayor Sadiq Khan committed to the city meeting the World Health Organisation PM2.5 guideline of 10ug/m3 by 2030, but this is the latest study to suggest that there is no ‘safe’ exposure to PM2.5.

Every year around 11,000 coronary heart disease and stroke deaths in the UK are attributable to particulate matter air pollution.

Jacob West, executive director of Healthcare Innovation at the British Heart Foundation said: ‘Air pollution is a major public health emergency and over many years it has not been treated with the seriousness it deserves. Unless we take radical measures now to curb air pollution, in the future we will look back on this period of inaction with shame.

‘As these figures show, the effect of air pollution on our heart and circulatory system is profound, and we have no choice over the air we breathe in the places we live.

‘Legislation was passed over a decade ago to protect people from passive smoke, and similarly decisive must be taken to protect people from air pollution.

‘The last government accepted that it is possible to implement tougher WHO air pollution limits, and the next government must now do so protect the health of the nation.’