In this article, our developed emission inventories of PAHs, REAS-POP and chemical transport model, RAQM2-POP, which cover Northeast Asian region, are introduced. Validities of RAQM2-POP and REAS-POP were confirmed by agreement with the other PAHs inventory in China and the observed PAHs concentrations in Northeast Asia. Simulated atmospheric concentration distributions of PAHs in Northeast Asia revealed that PAHs concentrations in Noto, Japan in winter were mainly dominated by biomass and coal combustion and coal transformation in China. On the other hand, those in summer were dominated by mobile sources in Japan. Our modeling study demonstrated importance of transboundary air pollution from the Asian continent in winter Japan. As for future issues, clarification of PAHs concentration distributions in Northeast Asia after recent emission controls from mobile and stationary sources in China will be necessary. Furthermore, atmospheric deposition distributions of PAHs and its impact on ecosystem in Northeast Asia should be elucidated.
