Highlights

•PM2.5-related mortality was assessed in relation to rapid population aging in Korea.

•The proportion of older adults (ages 65+) is projected to increase to 40% by 2050.

•Due to rapid aging, PM2.5-related mortality is expected to increase by 79,375 by 2050.

•To offset the aging impacts, PM2.5 levels need to decrease to 5.8 μg/m3.

Particulate matter with an aerodynamic diameter of ≤2.5 μm (PM2.5) can infiltrate deep into the respiratory system, posing significant health risks. Notably, the health burden of PM2.5 is more pronounced among the older adult population. With an aging population, the public health burden attributable to PM2.5 could escalate even if the current PM2.5 level remains stable. This study evaluated the number of deaths attributable to long-term PM2.5 exposure in the Republic of Korea between 2020 and 2050 and identified the PM2.5 concentration required at least to maintain the current PM2.5 health burden.

Conclusions

Our health impact assessment projects a substantial public health burden of PM2.5-related mortality due to rapidly aging populations in South Korea. Low birth rate and extended life expectancy are anticipated to substantially increase both the number and proportion of elderly populations for 2020–2050. In an age-specific analysis, the older adult population emerged as the predominant contributor to total mortality, accounting for approximately 83% in 2020 and 96% by 2050.