4:2 Fluorotelomer Sulfonate (4:2 FTS)
4:2 fluorotelomer sulfonate (4:2 FTS) is a polyfluorinated compound in the fluorotelomer sulfonate (FTS) series. Unlike perfluorinated PFAS, fluorotelomers contain some hydrogen atoms in their chains but still include fully fluorinated segments. 4:2 FTS has been detected in water supplies near sites where AFFF was used for firefighting. It can transform in the environment to produce fully perfluorinated compounds like PFBA. The short chain length means it is mobile and capable of traveling long distances in groundwater before degrading to other PFAS.
Where 4:2 FTS comes from
Common uses
- Firefighting foam (AFFF)
- Paper food packaging
- Carpet protection
- Textile coatings
Industries
- Firefighting
- Food packaging
- Textiles
Health effects of 4:2 FTS exposure
Short-term effects
- Limited direct toxicological data
Long-term effects
- Degrades to PFBA and other PFAS; indirect exposure risk
- Environmental persistence
Most vulnerable populations
- Communities near military bases and airports using AFFF
How to remove 4:2 FTS from drinking water
- Reverse osmosis
- 84% removal
- Activated carbon
- 62% removal
- Ion exchange
- 85% removal
Is 4:2 FTS in your water? – Enter your ZIP at KnowYourExposure to see your local EPA test results.