The inventory was developed using a top-down approach based on the PKU-FUEL-200718 and an updated EFPAHs database. Among the 64 fuel sub-types defined in the PKU-FUEL-2007,18 the category of crude oil (used in petroleum refinery) was replaced with catalytic cracking. In addition, five process emission sources in the iron-steel industry (iron sintering, open hearth furnace, convertor, arc furnace, and hot rolling) were added,23 increasing the total fuel sub-types to 69 (Table S1). They were divided into six categories (coal, petroleum, natural gas, solid wastes, biomass, and an industrial process category) or six sectors (energy production, industry, transportation, commercial/residential sources, agriculture, and deforestation/wildfire). PKU-PAH-2007 covered 222 countries/territories and was gridded to 0.1°× 0.1° resolution for the year 2007. In addition, annual PAH emissions from individual countries were derived from 1960 to 2008 and simulated from 2009 to 2030 based on the six IPCC SRES scenarios.24 The 16 PAHs included in the inventory were: naphthalene (NAP), acenaphthylene (ACY), acenaphthene (ACE), fluorene (FLO), phenanthrene (PHE), anthracene (ANT), fluoranthene (FLA), pyrene (PYR), benz(a)anthracene (BaA), chrysene (CHR), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(a)pyrene (BaP), dibenz(a,h)anthracene (DahA), indeno(l,2,3-cd)pyrene (IcdP), and benzo(g,h,i)perylene (BghiP). In this study, the term “total PAHs” means the sum of the 16 PAHs.