Air pollution is a threat to public health affecting both developed and developing countries, causing seven million deaths every year according to the WHO. More than 90% of the global population live in regions where pollution is above levels considered harmful for human health. Emergent economies are hit the hardest, as the problem gets particularly worrying where air quality regulation struggles to keep pace with rapid urbanisation and industrial development, usually sustained by massive combustion of fossil fuels and coal in particular.
Attention to the issue has been revived in the midst of the COVID-19 pandemic. On the one side, cleaner skies seen around the world as a consequence of total or partial lockdowns have been considered a silver lining to the pandemic. Beyond meaningful short-term results in these months, however, the slowdown in economic activity cannot (and should not) be considered a feasible solution to poor air quality in the longer run. On the other side, scientists have also been studying the “boost” effects of several pollutants – such as PM10, PM2.5 and NOx – whose high concentration in urban and industrialized areas like northern Italy or eastern and central China might have favoured the spread of the virus at greater distances and might have increased the exposure and severity of COVID-19 symptoms.