Ambient Air Quality Standards: International Differences in Limits to Acceptable Air Pollution (original) (raw)

Ambient air pollution causes millions of premature deaths globally every year. In the effort to combat air pollution, countries have legally formulated air quality standards (AQS) to divide ‘safe’ and ‘unsafe’ concentrations of a number of pollutants. The WHO Air Quality Guidelines serve as their reference point for the four criteria pollutants PM2.5 and PM10, O_3, NO_2, and SO_2, backed by largescale studies on health repercussions at a variety of concentrations. The current legal policy study compares the limit values set out in the European Union, the United States, China, and India, with each other as well as with the latest update of the WHO Guidelines, including Interim Targets for a gradual alignment with the sustainable pollution limits. This study also elaborates on the role and measurement of such standards, and touches upon compliance, monitoring, and reporting in the respective economies. It turns out that although the four case polities developed their AQS in similar time periods and refer to the WHO Guidelines, they vary significantly from these as well as the Interim Target values in many cases. Still, all four polities report frequent, or even regular, exceedance and address this with compliance mechanisms as set out in domestic policy. This has led to a slow improvement in air quality, but monitoring, enforcement, and public information leave broad gaps, particularly in China and India.