Emission and modelled spatial distribution of PAHs for the base year. (A) The average PAH emissions (Mg year⁻¹) in 2008–2010. The spatial distribution patterns of PAH concentrations in (B) air (ng m⁻³), (C) freshwater (ng L⁻¹), and (D) soil (ng g⁻¹) in the base year (2009) under the RCP4.5 scenario. Dark blue lines indicate four geographical regions of China, including North China, South China, Northwest China, and the Qingzang Gaoyuan. Light green lines indicate the provinces and cities where the “2 + 26” cities are located, including Beijing, Tianjin, Hebei, Shanxi, Shandong, and Henan. Data from Hainan and Taiwan are unavailable so that Hainan and Taiwan are uncolored in all the maps.