Mortality and morbidity consequences of particulate matter in South Korea: evidence from transboundary air pollution

Abstract

Abstract Background: Exposure to fine particulate matter (PM 2.5 ) is harmful to people, leading to respiratory disease and even death. The association between PM 2.5 pollution and health outcomes has become a key foundation for public health policy development. This study aims to quantify the effects of PM 2.5 on health outcomes (mortality, morbidity) and estimate the benefits of reducing PM 2.5 levels in South Korea. Methods: This study uses Instrumental Variable (IV) analysis to estimate the causal effect of PM 2.5 on health outcomes in South Korea from 2015 to 2022. Local air pollution in South Korea is instrumented using a wind-direction indicator with air pollution levels measured at upwind Chinese monitors to address potential endogeneity concerns. Estimates of PM 2.5 -related death and the life-year loss are used to calculate the economic benefits of preventing PM 2.5 -related deaths. Results: The results indicate that a 1 μg/m³ increase in local PM 2.5 levels drives a 0.17% rise in older (65+) adult mortality rate and a 5.1% increase in respiratory hospitalizations. Significant rises in mortality and morbidity were observed for disease categories directly associated with PM 2.5 pollution. Considering only the avoided life years lost, the 5.58 μg/m³ reduction in PM 2.5 levels achieved in South Korea from 2015 to 2022 resulted in an estimated USD 14.14 billion in annual benefits. The study also found that a 1 μg/m³ increase in PM 2.5 raised hospital visits by 1.2% for acute upper respiratory infections and 2.6% for lower respiratory infections. Conclusion: These findings highlight the magnitude and cost of the health risks posed by air pollution, underscoring the importance of effective policies to manage air quality. This study provides clear evidence of the harmful effects of air pollution on human health, particularly on vulnerable groups and related diseases.