Review of the impact of air pollution in Asian countries to support SDG target 3.9.1 toward renewable and sustainable energy growth

Air pollution poses a critical challenge to public health and environmental sustainability in South and East Asia, where rapid urbanization and industrial expansion have significantly contributed to atmospheric degradation. This study examines the spatiotemporal distribution, emission sources, and impacts of air pollution across 119 urban regions in six Asian countries: Bangladesh, Bhutan, China, India, Nepal, and Pakistan covering the period from 2012 to 2024. This research reviews existing policies, identifies major emission sources, and highlights persistent challenges along with country-specific mitigation strategies. Comparative trend analysis shows that significant reductions in pollutant levels across Chinese cities are the result of stringent emission control measures, while other countries continue to experience declines in air quality. Source attribution analysis, based on air pollutants and total GHG emissions including CO, NO_x, PM_2.5, SO₂, CH₄, CO₂, F-gases, and N₂O, identifies the energy and industrial sectors as dominant contributors in China and India, whereas agriculture remains a key emitter in Pakistan, Nepal, and Bhutan. The study further evaluates the public health burden linked to PM_2.5 exposure, revealing severe mortality risks in South and East Asia, especially among children and the elderly, from both ambient and household air pollution. This study aims to evaluate the impact of air pollution in one of the most polluted regions of the world through an integrated assessment that supports SDG Target 3.9.1 and proposes a framework for sustainable air quality governance in rapidly developing Asian economies. This study establishes a crucial foundation for renewable and sustainable air quality management across South and East Asia, with future directions including the integration of ground-based observations, machine learning predictions, and detailed evaluations of localized policy frameworks. The findings underscore the urgent need for region-specific, multi-sectoral mitigation strategies to reduce emissions and health burdens, thereby advancing sustainable air quality management aligned with SDG Target 3.9.1.