Quantifying the Source-Receptor Relationships of PM2.5 Pollution and Associated Health Impacts among China, South Korea, and Japan: A Dual Perspective and an Interdisciplinary Approach.

Abstract

Background: Transboundary particulate matter (PM) with aerodynamic diameter $\le 2.5\mu m$ (${\mathrm{PM}}_{2.5}$) pollution is causing significant environmental conflicts among China, South Korea, and Japan. However, efforts to address these conflicts have been impeded by a lack of a comprehensive understanding of source-receptor relationships of ${\mathrm{PM}}_{2.5}$ pollution and associated health impacts among these countries.

Objectives: We quantified the extent to which transboundary ${\mathrm{PM}}_{2.5}$ pollution and associated health impacts are mutual among the three countries in 2015 and 2017 using three metrics (population-weighted mean ${\mathrm{PM}}_{2.5}$ concentration, ${\mathrm{PM}}_{2.5}$ population exposure, and ${\mathrm{PM}}_{2.5}$-related premature deaths) and two accounting perspectives (production and consumption).

Methods: We adopted an integrated interdisciplinary analysis framework that links an environmentally extended multiregional input-output model, a GEOS-Chem chemical transport model, a population exposure model, and an exposure-response model.

Results: From a production perspective, China's contributions to population-weighted mean ${\mathrm{PM}}_{2.5}$ concentrations in South Korea and Japan were considerable, whereas the contributions of South Korea and Japan to China were negligible. However, the contributions from South Korea and Japan to ${\mathrm{PM}}_{2.5}$ population exposure and associated premature deaths in China were nonnegligible from both production and consumption perspectives. From a consumption perspective, the contributions of South Korea and Japan to ${\mathrm{PM}}_{2.5}$-related premature deaths in China amounted to $6.96$ [95% confidence interval (CI): 6.36, 7.56] and $9.79$ (95% CI: 8.93, 10.64) thousand deaths in 2015, respectively, and $5.03$ (95% CI: 4.55, 5.49) and $7.75$ (95% CI: 7.02, 8.47) in 2017, respectively. These figures were generally larger than China's contributions to ${\mathrm{PM}}_{2.5}$-related premature deaths in South Korea and Japan, which totaled $4.63$ (95% CI: 3.97, 5.28) and $3.91$ (95% CI: 2.78, 5.01) thousand deaths in 2015, respectively, and $4.43$ (95% CI: 3.75, 5.1) and $3.69$ (95% CI: 2.57, 4.79) in 2017, respectively.

Discussion: Our findings show that mutual contributions of ${\mathrm{PM}}_{2.5}$ pollution and associated health impacts among the three countries varied considerably when different metrics and accounting perspectives were applied. A consumption perspective revealed narrower gaps in mutual contributions than a production perspective. Moreover, other countries outside Northeast Asia may have played a significant role in contributing to ${\mathrm{PM}}_{2.5}$ pollution and associated health impacts in Northeast Asia, suggesting that Northeast Asian countries should look beyond this region and collaborate with the rest of the world to jointly develop effective ${\mathrm{PM}}_{2.5}$ mitigation strategies. Our findings could help policymakers, scholars, and the public in China, South Korea, and Japan understand the intricacies involved in assigning environmental responsibilities and achieving environmental justice with respect to transboundary ${\mathrm{PM}}_{2.5}$ pollution. https://doi.org/10.1289/EHP14550.