Spatiotemporal patterns and functional implications of PFAS in fresh tea leaves from Hangzhou, China: Dominant trifluoroacetic acid and diminished antioxidant activity.

Per- and polyfluoroalkyl substances (PFAS) pose persistent and widespread risks to agroecosystems and food quality, yet their impact on tea (Camellia sinensis L.) functional quality remains unclear. We analyzed 41 PFAS, including the ubiquitous ultrashort-chain congener trifluoroacetic acid (TFA), in 54 tea samples from Hangzhou, China. TFA was the dominant congener, most PFAS were higher in autumn than spring, and TFA accumulated more in tea from mountain slopes. Principal component regression and mediation analyses revealed negative correlations between PFAS burden and tea functional quality, with decreased catechins (e.g., epigallocatechin gallate) potentially mediating diminished antioxidant activity. Metabolomic associations suggested that PFAS-related phenylpropanoid pathway disruption may deplete catechins. Although direct dietary exposure risks were low even for heavy consumers, PFAS contamination may compromise the functional quality and health benefits of tea, underscoring the need for targeted mitigation. Nevertheless, the mechanistic inferences and causality remain to be validated by further studies.