Abstract

Abstract Air pollution poses a critical environmental challenge to sustainability, environmental health and public well-being in the South Asia Region (SAR). This study identifies hotspots of fine particulate matter (PM2.5) across SAR, analyzing both concentration levels and exposure. Moreover, it aims at a comprehensive understanding of the various sources of air pollution in these critical areas and a systematic evaluation of the costs and benefits of relevant policy actions, utilizing the GAINS modeling framework. A wide variety of sources contribute to PM2.5 levels in ambient air, and effective air quality management requires a balance of measures across these sources. Current environmental policies, while effective in decoupling emissions from economic growth in SAR, are insufficient to achieve significant reductions in ambient PM2.5 concentrations. However, considerable scope exists for further measures beyond current policies that could help to bring the WHO Interim Targets (IT-1) for PM2.5 closer. Finally, it is shown that cost-optimal strategies for air quality management can achieve significant cost savings compared to conventional approaches; however, they require collaboration between states, regions and countries in South Asia.