The extensive use of per- and polyfluorinated substances (PFASs) and their substitutes has resulted in their frequent detection in environmental matrices. However, limited information is known about their uptake into vegetables and health risk through diet, particularly for those emerging alternatives. In this study, a total of 17 PFASs (namely 12 legacy PFASs and 5 of their alternatives) were compared for their accumulation into four staple vegetables (lettuce, Chinese cabbage, chrysanthemum coronarium and cucumber) grown in hydroponic system. The sum concentrations of 17 PFASs in edible parts were in the order of Chinese cabbage leaf (13456 ng/g)＞lettuce leaf (5996 ng/g )＞cucumber fruit (4115 ng/g)＞chrysanthemum coronarium stem (3999 ng/g). For PFOA and its alternatives, HFPO-TA preferentially accumulated in roots than PFOA with root concentration factors of 35.7-99.9. Translocation to edible parts was more extensive for HFPO-DA with significantly (p<0.05) higher concentrations than PFOA in lettuce and cucumber. For PFOS and its alternatives, roots of all the four vegetables were found to more readily accumulate 8:2 Cl-PFESA than PFOS, but 8:2 Cl-PFESA was hardly translocated to the aerial parts. Significantly (p<0.05) higher edible concentrations of 8:2 FTSA or 6:2 FTSA than PFOS were observed for cucumber. Daily exposure to the 17 PFASs through the consumption of mature vegetables was estimated. The intake doses of some novel PFASs (e.g., 8:2 FTSA with values of 4.80, 10.6, 0.30 ng/kg_{body weight}) were higher than its legacy counterpart (i.e., PFOS with estimated exposure values of 4.08, 5.62, 0.15 ng/kg_{body weight}) in lettuce, Chinese cabbage, and cucumber. The appreciable accumulation of these emerging PFASs in vegetables raised the concerns about their safety as alternatives for legacy PFASs.

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