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Perfluorinated Chemicals (PFAS)
Perfluorooctane sulfonate PFOS
PFOS is a synthetic perfluoroalkyl substance formerly used in stain repellents, firefighting foams, and various industrial applications. It is environmentally persistent and bioaccumulative with recognized toxicity concerns. Not a food ingredient, primarily a chemical contaminant with no safe consumption role.
Tracked contaminantUpdated Aug 28, 2025
Health score-5.0
-5Very bad5
Water guidelines
- Legal limit
- 0.000004 ppm
- Health guideline
- 2e-9 ppm
Food and supplement guidelines
- Legal limit
- Not specified
- Health guideline
- Not specified
Risks
Environmental persistence, bioaccumulation, potential carcinogenicity, developmental toxicity, immune system effects, endocrine disruption, neurotoxicity
Benefits
None