Are Coldstream cartridges effective at filtering PFAS?
Are Coldstream FTO+ filters effective at removing PFAS, including PFOA and PFOS?
Yes, Coldstream FTO+ filters have proven to be exceptionally effective in reducing PFAS, a class of persistent chemical contaminants, including PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonate).
According to Coldstream's lab tests , FTO+ filters have reduction rates of over 99.9%.
These results confirm that FTO+ filters are particularly suitable for removing these substances, which are known for their persistence in the environment and their potentially harmful effects on human health.
What evidence supports the performance of Coldstream FTO+ filters in reducing PFAS?
Laboratory test results of the Coldstream FTO+ and ProOne G2.0 filters (*), which shared the same technologies until the end of 2024 thanks to KLT Filtration, confirm a 99.9% reduction in PFAS, including PFOA and PFOS.
This performance is due to the use of advanced ceramic and high-quality activated carbon.
Prior to Culligan's acquisition of ProOne, ProOne filter cartridges were actually Coldstream FTO+, manufactured by KLT Filtration and remanufactured under the ProOne brand. Since January 2025 ProOne cartridges are no longer manufactured exclusively by Coldstream, KLT and therefore no longer have Coldstream quality. However, the ProOne laboratory tests that we invite you to read at the end of the article date from 2015 and 2021, so they do concern the FTO+ Coldstream technology.
The cross-referencing of data between Coldstream and ProOne validates the effectiveness of these filters against a wide range of persistent chemical contaminants, enhancing their credibility and reliability.
Can FTO+ filters also reduce TFAs (trifluoroacetic acids)?
Coldstream FTO+ filters have demonstrated a very high reduction in medium and long chain PFAS (including PFOA and PFOS), in excess of 99%, according to independent laboratory testing on the twin ProOne G2.0 cartridge – made from the same ceramic and activated carbon base by KLT Filtration (UK and USA).
These tests confirm the media's ability to adsorb the most common PFAS through the combination of a microfilter ceramic and a specific activated carbon with a very large surface area.
Regarding TFA (trifluoroacetic acid), the situation is different:
- TFA is a much smaller and hydrophilic molecule than other PFAS.
- Activated carbon can partially reduce the concentration under certain conditions (long contact time, acidic pH, mineral microporous carbon), but the effectiveness remains variable and not constant over time.
- No gravity technology (regardless of brand) can guarantee complete removal of TFA; Only a reverse osmosis or selective ion exchange system allows total retention.
In summary, Coldstream FTO+ filters provide a strong reduction in common PFAS (C4–C12), but TFA is not officially claimed to date because its complete filtration is not feasible by gravity alone.
Do FTO+ filters also reduce other chemical contaminants?
Yes. In addition to PFAS, Coldstream FTO+ filters have a rare capability among gravity filters:
- Fluoride: 97.5% reduction at start-up, still close to 90% at 500 L
- Nitrate: 98% reduction initially, maintained at approximately 60% after 3000 L based on IAPMO/Envirotek testing on the CF163W.
This performance reflects the quality of the ceramic + activated carbon media developed by KLT Filtration, which is capable of acting on both dissolved chemical pollutants (fluorine, nitrates, PFAS) and microbiological contaminants (bacteria, viruses, parasites).
Where can I see the lab test results of FTO+ filters for PFAS reduction?
You can view the results of the laboratory tests of FTO+ filters for PFAS reduction by following these links:
For any information or question, please do not hesitate to contact our customer service by e-mail at the following address: info@pure-filters.com.