WHO Air Quality Guidelines and other information resources
Has outdoor air quality, particularly in major cities, improved since the first WHO Air Qualtiy Guidelines was issued in 1987?
Levels of outdoor air quality in developed country cities have improved substantially in the 1990s, but less so since the year 2000. This is partly due to the increase in the number and power of motor vehicles as well as the ever growing need for power generation.
Since the initial set of WHO Guidelines (1987), there are notable examples showing improvements in health following specific policy interventions to improve outdoor air quality. For example, in 1990, the Irish government banned the marketing, sale and distribution of coal in Dublin. Soon after the ban, significant reductions in particulate matter (i.e. black smoke) were observed as well as a reduction in mortality from cardiovascular and respiratory diseases. Similar reductions in mortality were seen in Hong Kong after regulations were put into place which required power plants and vehicles to use fuel with lower sulfur content. Implementation of the air quality regulations contributed 15% to overall increased life expectancy observed in the United States between 1980 and 2000.