Co-benefit or tradeoff? The impact of inter-provincial trade-embodied pollutants on air quality and public health under climate targets in China

Abstract

Trade-embodied pollutants significantly impact air quality and and public health across regions, particularly under climate policy constraints, yet their transboundary health impacts via inter-regional trade remain underexplored. To address this, this study integrates a general equilibrium model, an air quality model, and health impact model to assess how interprovincial trade redistributes PM₂.₅ and health burdens between China's Chuan-Yu zone (Sichuan-Chongqing) and their trade partner regions under business-as-usual (BaU) and 1.5 °C scenarios. The findings indicate that CO₂ emissions in the Chuan-Yu zone follow an inverse U-shape pattern, peaking earlier under the 1.5 °C target than the BaU scenario, with Chongqing (133.94 Mt, 2017) achieving peak emissions 5–8 years before Sichuan (318.79 Mt, 2025). While SO₂ shows the sharpest decline, agricultural NH₃ remains challenging to mitigate. Trade shifts redistribute PM_2.5 pollution under the 1.5 °C target, with Shaanxi, Liaoning, and Hubei as inflow regions and Shanghai, Beijing, and Jiangsu as outflow regions. Notably, PM_2.5 concentrations rise in Jiangsu, Zhejiang, and Guangdong as they absorb production originally from Chuan-Yu. Stricter climate targets exacerbate spatial and temporal inequalities in Chuan-Yu's morbidity and mortality rates. Strikingly, health inequalities intensify spatially duto to trade, with Chongqing benefiting from shifted pollution burdens while Sichuan facing higher mortality. Stroke and ischemic heart disease (IHD) remain leading mortality causes, with significant reductions projected by 2060 in developed regions like Shanghai, Jiangsu, and Beijing, though the decline is slower in Inner Mongolia and Heilongjiang. The findings underscore the necessity for spatially differentiated governance, advocating for province-level pollution offset mechanisms and health compensation funds to address trade-induced disparities.