The World Health Organization (WHO) says 97% of cities in low- and middle income countries with more than 100 000 inhabitants do not meet WHO air quality guidelines.
In it’s 2018 report, the global health body notes that in high-income countries, that percentage decreases to 49%.
In the past two years, the database – now covering more than 4000 cities in 108 countries – has nearly doubled, with more cities measuring air pollution levels and recognizing the associated health impacts.
As urban air quality declines, the risk of stroke, heart disease, lung cancer, and chronic and acute respiratory diseases, including asthma, increases for the people who live in them.
WHO also noted that more than 80% of people living in urban areas that monitor air pollution are exposed to air quality levels that exceed the World Health Organization (WHO) limits.
Delhi, India and Cairo, Egypt have the worst PM10 pollution levels out of the world’s megacities (over 14 million people), but Argentina, Brazil, China, Mexico and Turkey all have cities in the top-ten list of most-polluted places.