WHO: 99% of global population breathes unhealthy air
5 April 2022
Almost the entire global population, 99%, breathes air that exceeds WHO air quality limits and threatens their health, according to the World Health Organization’s (WHO) air quality database. A record number of over 6,000 cities in 117 countries are now monitoring air quality, but the people living in them are still breathing unhealthy levels of fine particulate matter (PM2.5) and NO2, with people in low and middle-income countries suffering the highest exposures.
The 2022 update of the WHO’s air quality database introduces, for the first time, ground measurements of annual mean concentrations of NO2, a common urban pollutant and precursor of particulate matter and ozone. It also includes measurements of PM10 and PM2.5. Both groups of pollutants originate mainly from human activities related to fossil fuel combustion, according to the WHO.
“Current energy concerns highlight the importance of speeding up the transition to cleaner, healthier energy systems,” said Dr Tedros Adhanom Ghebreyesus, WHO Director-General. “High fossil fuel prices, energy security, and the urgency of addressing the twin health challenges of air pollution and climate change, underscore the pressing need to move faster towards a world that is much less dependent on fossil fuels.”
WHO last year revised its Air Quality Guidelines, making them significantly more stringent. The WHO limit for PM2.5 was reduced from 10 µg/m3 to 5 µg/m3. The guideline for annual NO2 exposure was tightened from 40 µg/m3 to 10 µg/m3.
In the 117 countries monitoring air quality, the air in 17% of cities in high-income countries fall below the WHO’s guidelines for PM2.5 or PM10 exposure. In low- and middle-income countries, air quality in less than 1% of the cities complies with WHO recommended thresholds.
Globally, low- and middle-income countries still experience greater exposure to unhealthy levels of PM compared to the global average, but NO2 patterns are different, showing less difference between the high- and low- and middle-income countries.
About 4000 cities/human settlements in 74 countries collect NO2 data at ground level. Aggregated, their measurements show that only 23% of people in these places breathe annual average concentrations of NO2 that meet the updated WHO guideline of 10 µg/m3.
The WHO announcement follows the recent report by the Swiss air quality technology company iQAir, which found that only three percent of cities and not a single country met the updated WHO PM2.5 air quality guideline in 2021.
Source: WHO