Legacy and Novel Per- and Polyfluoroalkyl Substances in Surface Soils across China: Source Tracking and Main Drivers for the Spatial Variation

China aims to actively control the contamination of globally
concerning
per- and polyfluoroalkyl substances (PFASs). Evaluation of the current
situation can provide a critical reference point for tracking the
effectiveness of ongoing progress. Herein, we present the first comprehensive
assessment of the spatial variations of 20 legacy and 54 novel PFASs
in Chinese background soils in 2021. Novel PFASs were extensively
detected in 98.4% of the samples, with 21 species being first reported,
which greatly facilitated the appointment of diverse emission sources
that aligned with local industrial structures. However, legacy PFASs
still dominated the ∑74PFAS profile (median 0.51
ng/g, 0.050–8.33 ng/g). The spatial heterogeneity of soil PFASs
was positively driven by economic development and atmospheric deposition,
enabling the establishment of predictive models to project the national
distribution and temporal trends. Elevated PFAS levels were predominantly
distributed in the more industrialized eastern and southern regions,
as well as other coastal areas with greater precipitation. ∑74PFAS in surface soils was estimated to increase by 12.9 pg/(g
year) over 2002–2021, which would continue alongside economic
growth, albeit with greater contributions from novel alternatives.
Our work provides comprehensive baseline and predictive data to inform
policies toward PFAS control in China.