World Health Organization - Air quality in most cities worldwide that monitor outdoor (ambient) air pollution fails to meet WHO guidelines for safe levels, putting people at additional risk of respiratory disease and other health problems.
WHO’s urban air quality database covers 1600 cities across 91 countries – 500 more cities than the previous database (2011), revealing that more cities worldwide are monitoring outdoor air quality, reflecting growing recognition of air pollution’s health risks.
Only 12% of the people living in cities reporting on air quality reside in cities where this complies with WHO air quality guideline levels. About half of the urban population being monitored is exposed to air pollution that is at least 2.5 times higher than the levels WHO recommends - putting those people at additional risk of serious, long-term health problems.
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