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4:2 FTSA
4:2 Fluorotelomer sulfonic acid (4:2 FTSA) is a perfluoroalkyl substance (PFAS) used as a degradation product and precursor to longer-chain PFAS compounds. It is not a food ingredient but a chemical material often detected as an environmental contaminant with persistence and bioaccumulative potential.
Tracked contaminantUpdated Feb 6, 2026
Health score-5.0
-5Very bad5
Water guidelines
- Legal limit
- Not specified
- Health guideline
- Not specified
Food and supplement guidelines
- Legal limit
- Not specified
- Health guideline
- Not specified
Risks
Environmental persistence, bioaccumulation, potential toxicity, endocrine disruption, carcinogenicity concerns
Benefits
None