The recently published 2023 World Air Quality Report from Swiss technology company IQAir reveals some stark facts about the level of pollution in cities and countries across the world.

According to the World Health Organization (WHO), air pollution poses a major threat to health and climate. Over seven million people die prematurely every year from exposure to fine particulate matter – dust, soot, dirt and smoke – caused by both ambient and household air pollution.

To meet WHO guidelines, this fine airborne particulate matter (PM2.5), which is less than 2.5 micrometres in diameter, should not exceed 5 micrograms per cubic metre (µg/m3).

In its latest 2023 World Air Quality Report, IQAir published region and city PM2.5 rankings. To do this it analysed data from more than 30,000 air quality monitoring stations across 7,812 locations in 134 countries, territories and regions.

The report found that only seven countries met the WHO annual PM2.5 guideline: Australia, Estonia, Finland, Grenada...