Per- and polyfluoroalkyl substances (PFASs) have been extensively studied across various environmental compartments in the global ocean. Current research reveals that PFASs are ubiquitous, earning their reputation as "forever chemicals" even in the remote polar environments. Long-range environmental transport via atmospheric circulation and oceanic currents are key pathways through which PFASs globally distributed. In seawater and snow, perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), and short-chain perfluorinated alkyl acids (C4–C6 PFAAs) are the predominant compounds, while perfluoroundecanoic acid (PFUnDA), perfluorononanoic acid (PFNA) and PFOS dominate in polar biota. Emerging PFASs, such as hexafluoropropylene oxide dimer acid (HFPO-DA) and fluorotelomer sulfonates (6:2 and 8:2 FTS), have also been detected, despite their relatively recent use as replacements for legacy PFASs. Spatial distributions suggest declining PFAS concentrations with increasing distance from continental sources, indicating ongoing discharge and transport processes. Neutral PFASs favor atmospheric transport and can transform into ionic forms through photochemical and biodegradation processes, which can be important source of ionic PFASs in the remote ocean and polar regions. Elevated PFAS concentrations in Arctic and Antarctic coastal areas highlight the role of glacier melt and sea ice retreat as secondary sources. Given the impacts of climate change, future research should integrate observations and models to better understand PFAS biogeochemical cycles in polar regions.
Keywords: Per and polyfluorinated alkyl substances, Ocean, Arctic, Antarctica, Long-range transport, atmosphere, seawater
 

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