A huge segment of the world’s population that reaches 99% breathes unhealthy air that exceeds the air quality limits set by the World Health Organization (WHO) and threatens its health.
Already more than 6,000 cities in 117 countries, a record number, monitor air quality, but people living in them are still breathing unhealthy levels of fine particles and nitrogen dioxide, with people in low- and middle-income countries suffering the highest exposure.
The findings prompted the World Health Organization to stress on Monday the importance of curbing the use of fossil fuels and taking other concrete measures to reduce air pollution levels.
Higher income countries have lower particulate pollution, but have problems with nitrogen dioxide
In the 117 countries that monitor air quality, air in 17% of cities in high-income countries falls below who’s air quality guidelines for PM 2.5 or PM 10. In low- and middle-income countries, air quality in less than 1% of cities complies with the WHO’s recommended limits.
Globally, low- and middle-income countries still have a greater exposure to unhealthy PM levels than the global average, but NO2 standards are different, showing less difference between high- and low-income and middle-income countries.
About 4,000 cities (human settlements) in 74 countries collect NO2 data at the ground level. Overall, their measurements show that only 23% of people in these places breathe average annual NO2 concentrations that meet the levels in the recently updated version of the WHO’s Air Quality Guidelines.
Europe and, North America, remain the regions with the most comprehensive air quality data. In many low- and middle-income countries, while PM 2.5 measurements are not yet available, they have seen big improvements in metrics between the last database update in 2018 and this, with an additional 1500 settlements in those countries monitoring air quality.