Emissions of Respirable Magnetite from the Coal-Fired Power Sector in China: Spatial Inequalities and Mitigation Pathways

Magnetite particles, being ubiquitous and highly abundant in the atmosphere, have raised notable cardiovascular and neurodegenerative health risks globally. However, the limited understanding of their emissions hinders the targeted mitigation. Here, we developed a multifactor emission modeling framework to evaluate magnetite emission from the coal-fired power sector in China, one of the most sizable contributors to airborne magnetite, and identify policy-effective mitigation pathways. Total atmospheric emissions of respirable magnetite are 2,828.7 (2,307.1-3,371.4) t per year, exhibiting distinct spatial inequalities driven by tiered emission standards. Despite contributing only 4% of national coal-fired power, two superemitting provinces, Guizhou and Sichuan, could reduce over 31% of the national magnetite emission by tightening their emission standards, highlighting that targeting hotspots regions represents a highly efficient pathway to substantial mitigation benefits. These findings can facilitate policy-making for achieving targeted magnetite mitigation and provide transferable insight for air pollution control in other countries globally.