Climate Action Impacts on Steelmaking Emissions of Persistent Organic Pollutants Highlight a Gap Between the Paris Agreement and the Stockholm Convention.

Global warming and unintentionally produced persistent organic pollutants (UPOPs) are well-recognized global concerns. Climate action under the Paris Agreement and UPOPs control under the Stockholm Convention proceed on separate tracks. Evidence of shared health gains is limited. Global steelmaking is a measurable case. Route-specific UPOPs emission factors and projected changes in output and technology are integrated to estimate 2019-2050 global and regional emissions. Atmospheric and lifetime inhalation-risk models then quantify added lifetime cancer risk from steelmaking UPOPs. Under climate action, emissions of UPOPs decline by 2050. Yet cancer-risk inequality persists. Risk shifts from traditional hubs to emerging regions-India, the Middle East, and Africa-where some areas reach 270%-490% of 2019 levels. By 2050, India shows the largest added cancer burden (2201 additional cases). Health-risk gains are about half the carbon gains; in some regions (e.g., the Middle East, Africa), risk increases even as carbon intensity falls. These findings indicate that current climate action should be complemented by targeted UPOPs controls and a policy bridge between the Stockholm Convention and the Paris Agreement to advance global health and equity. The study provides a data basis for aligning global environmental governance and strategy-making to advance global health and equity.