Multi-level governance for improving air quality in cities in the UNECE region: a science policy perspective

Abstract

Air pollution is the most harmful environmental risk factor to human health. Cities with high population density and associated high levels of air pollution offer a unique opportunity to significantly improve public health. The major sources of air pollution in cities differ from city to city and from pollutant to pollutant. In most cities combustion from residential heating or transport are the most relevant local sources of primary particulate matter and nitrogen dioxide. Other significant sources lie outside cities. The diversity of sources and pollutants means that no single government body can implement measures on its own to sufficiently improve the air quality to meet the air quality guideline levels of the WHO. Cross-governmental collaboration is also needed, because measures that reduce emissions in a wider region could deliver greater health benefits, by reducing the average exposure, than local measures targeting hotspots. Local information on sources as well as air quality monitoring and modelling are essential to assess which sectors are most relevant for each city. The most effective combination of policies to improve the air quality depends on the local context, the pollutant and its sources, but in all cases collaboration across government levels is essential. We give examples of how these levels of air quality management interact, which sources are most relevant and which pollutant-specific features should be considered in multi-level governance. Synergies across different policy areas, notably between climate, transport and air quality policies, offer various benefits among other environmental issues, e.g. urban planning and noise pollution. © 2026 The Authors.