Spatiotemporal inventory of PFOS and PFOA in China’s air, water and soil (2016–2021): Sharp declines yet persistent hotspots

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are persistent organic pollutants regulated under the Stockholm Convention, yet their national emission trajectories and spatiotemporal dynamics in China remain poorly constrained. Here we develop a bottom-up, consecutive 0.1-degree inventory across air, water, and soil from 2016 to 2021, showing that China’s PFOS emissions declined by 89%, from 49 (40–55) to 5.2 (4.3–5.9) t yr −1 , while PFOA emissions fell by over 99%, from 75 (62–90) to 0.31 (0.25–0.37) t yr −1 . These sharp declines coincided with regulatory restrictions and technological transitions across fluoropolymer manufacturing, metal plating, aqueous film-forming foams, and sulfluramid pesticides. The decline also reshaped the spatial structure of releases, shifting the emission profile from geographically dispersed pesticide and industrial use toward localized clusters at industrial and firefighting sites. Water remained the principal receiving medium (60% for PFOS and 71% for PFOA), and residual hotspots overlapped with dense populations in eastern and southeastern industrial zones. This inventory provides a quantitative basis for multimedia fate modeling, hotspot mitigation, and policy evaluation.