Occurrence of\nUltrashort-Chain PFASs in Australian\nEnvironmental Water Samples

Ultrashort-chain per- and polyfluoroalkyl substances\n(PFASs) are\nan emerging class of contaminants that remain underexplored in environmental\nresearch. This study examines their distribution in Australian drinking\ntap water, environmental waters, and wastewaters (n = 63) using nontarget\nanalysis via high-resolution mass spectrometry. Thirteen ultrashort-chain\nPFASs were identified, including novel compounds such as perfluoroalkane\nsulfinate (PFPSi), hydrogen-substituted perfluoroalkyl carboxylate\n(H-PFCA), chloro-perfluoroalkanesulfonate (Cl-PFSA), and bis-perfluoroalkyl\nsulfonamide (bis-FASIs). Perfluoropropanesulfonic acid (PFPrS) was\nthe most prevalent, detected in 83% of surface, groundwater, and wastewater\nsamples, and in 67% of tap water samples from major Australian cities.\nConcentrations of PFPrS and perfluoroethanesulfonic acid (PFEtS) ranged\nfrom <0.02 to 8000 ng/L. Ultrashort-chain perfluoroalkane sulfonamides\n(FASAs) and perfluoroalkane sulfates (PFA-OS) were predominantly found\nin wastewater. These findings highlight the widespread presence of\nultrashort-chain PFASs in Australian water systems and underscore\nthe need for ongoing monitoring and research due to their potential\necological and human health impacts. This study provides essential\nbaseline data that could inform future regulatory measures and environmental\nmanagement strategies.