Filthy air caused half a million early deaths in Europe in 2014. “Air pollution is the single largest environmental health risk in Europe,” says the European Environment Agency (EEA).  By far the biggest killer was PM2.5 pollution: tiny particles measuring 2.5 micrometres across or less. These caused 428,000 early deaths across the 41 European countries tracked in 2014. The main source, releasing 57 per cent of these emissions in 2015, was domestic wood burning.  Nitrogen dioxide, mostly from vehicle exhausts, cut short an estimated 78,000 lives across those countries. Ground-level ozone was the other major killer, taking 14,400 lives prematurely.

“Heart disease and stroke are the most common reasons for premature death attributable to air pollution, and are responsible for 80 per cent of cases,” the EEA says. Air pollution also worsens respiratory diseases and cancer, and has non-lethal impacts on diabetes, Alzheimer’s disease, pregnancy and brain development in children.

The main hotspots for PM2.5 pollution were Poland and northern Italy, where dozens of cities broke the European Union’s annual mean limit of 25 micrograms of particles per cubic metre of air. Poland and the Po valley have very bad pollution, the worst offender being Crakow, Poland. In all, 7 to 8 per cent of Europe’s urban population were exposed to PM2.5 levels above the EU limit. But under the World Health Organization’s stricter limit of 10 micrograms per cubic metre, this rose to 82 to 85 per cent.

Emissions are slowly falling, and this could be sped up by limiting vehicle numbers, burning cleaner fuels and boosting pedestrianisation. Adapting roads and buildings to suit cycling is also recommended. The answer is electric vehicles, but then the power has to be generated to begin with. I walk everywhere I can, but there is little pleasure in walking the streets of any large town at the moment.