Analysis of the National Air Pollutant Emissions Inventory (2021) in the Republic of Korea

In the Republic of Korea, air pollutant emissions are annually estimated and published. These emissions are used to formulate and evaluate national air quality policies. In this study, the 2021 National Air Pollutant Emissions Inventory in the Republic of Korea was estimated. In addition, emission sources and primary causes affecting changes in emissions were analyzed. As a result, air pollutant emissions in the Republic of Korea were 57,317 tons of PM-2.5, 160,993 tons of SOx, 884,454 tons of NOx, 1,002,810 tons of VOCs, and 262,008 tons of NH₃. PM-2.5, SOx, and NOx emissions in 2021 were lower than those in 2020 because of the reduction policy effects, such as the shutdown of old coal-fired power plants and stricter emission standards in workplaces. However, emissions of VOCs and NH₃ in 2021 increased those in 2020 due to socioeconomic effects, particularly in everyday activity sector. Specifically, it was caused by increased use of paint for construction and shipbuilding to meet rising demands as well as a rise in cattle numbers due to increased meat consumption. Spatially, Gyeonggi-do had the highest emissions of PM-2.5, NOx, and VOCs due to its dense populations and heavy traffic, while Ulsan and Chungcheongnam-do had the highest emissions of SOx and NH₃ from production process in their large national industrial complexes.