6. UK
EPI: 79.89
CO2 emission:6.49
PM2.5: 12.1
Air pollution, as we have seen, is the worst in urban areas of course. Britain, the number 6 on our list of least polluted countries in the world in 2018 is not an exception to this either, having three-quarters of worst air pollution hotspots being in London. But it seems that levels of air pollution are getting slightly lower in recent times.