Impact of polycyclic aromatic hydrocarbon (PAH) emissions from North Korea to the air quality in the Seoul Metropolitan Area, South Korea

Due to its proximity to the Seoul Metropolitan Area (SMA) (40 km from Seoul proper to North Korea) and the characteristics of energy consumption (coal and biomass burning as major primary energy sources), air pollutants emitted from North Korea are likely to influence the air quality in the SMA. To understand the transport of air pollutants emitted from North Korea, backward trajectories arriving in Seoul were estimated and classified into four cases depending on which area the trajectories predominantly passed through for the sampling days between 2002 and 2003. The ambient data of particulate polycyclic aromatic hydrocarbons (PAHs) were analyzed for the samples. Then, based on the contribution of biomass burning calculated by the chemical mass balance (CMB) model applied and the influence of air pollutantsʹ emissions from North Korea to SMA is semi-quantified. The result was verified by the spatial and seasonal variations of the PAH emission in China based on the previous works. It is estimated that the influence from North Korea on the particulate PAHs concentration in Seoul was up to 20% of the observed values. Further study directions are discussed to make more quantitative and reliable estimation.