Are Coldstream cartridges effective at filtering PFAS?
Are Coldstream FTO+ filters effective at removing PFAS, including PFOA and PFOS ?
Yes. Coldstream FTO+ filters have demonstrated a very high reduction in PFAS, a category of persistent chemical contaminants that includes PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonate).
The available data comes from the ProOne G2.0 twin cartridge, manufactured by KLT Filtration on the same high-density ceramic + activated carbon base as FTO+. Tested under the NSF/ANSI Standard 53 By an accredited independent laboratory, this cartridge reduces torque PFOA + PFOS below the regulatory threshold of 0.07 μg/L over its entire lifetime — a result in accordance with this reference standard.
In other words: FTO+ filters are particularly suited to reduce 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 ?
Two sets of Laboratory Tests independent cartridges, made on the ProOne G2.0 cartridge, confirm this:
- NSF/ANSI 53 Substandard (QFT Laboratory Report, 2020) : the reduction achieved about 96 to 98% for PFOA and more than 98.9% for PFOS, the remaining PFOA + PFOS pair below the threshold of 0.07 μg/L at each measurement step, over the entire filtration cycle (200 gallons / 100% capacity). This is the most demanding result, as it is measured over the entire life of the cartridge, not just at start-up.
- Wide Scan (Envirotek Report, 2015) : a reduction greater than 99.9% measured for PFOA, PFOS and several related compounds (PFBS, PFHxA, PFNA, PFHxS, PFDA), at an input concentration of 1.0 μg/L.
This performance is due to the combination of advanced microfilter ceramics and high-quality activated carbon with a very large adsorption surface.
For the sake of transparency, it should be noted that some emerging very short-chain PFAS (such as GenX) show a more variable reduction depending on the volume filtered. As with the TFA (see below), we prefer to say this clearly rather than promise everything.
Why mention ProOne ? Before Culligan's acquisition of ProOne, ProOne filter cartridges were actually Coldstream FTO+: manufactured by KLT Filtration, then remanufactured under the ProOne brand. As of January 2025, ProOne cartridges are no longer manufactured by KLT and therefore no longer have Coldstream quality. On the other hand, the ProOne laboratory reports that we invite you to consult at the end of the article date from 2015 and 2020 : they therefore concern the original Coldstream FTO+ technology.
The cross-referencing of this independent data validates the effectiveness of FTO+ filters against a wide range of PFAS, and reinforces their credibility pending the upcoming release of PFAS tests performed directly on the Coldstream FTO+ cartridge.
Can FTO+ filters also reduce TFAs (trifluoroacetic acids) ?
Filters Coldstream FTO+ have demonstrated a very high reduction in medium- and long-chain PFAS: greater than 98.9% for PFOS and in the range of 96-98% for NSF/ANSI 53 PFOA, according to tests carried out by independent laboratories on the twin ProOne G2.0 cartridge — manufactured on 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, as 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.
These performances reflect the quality of the ceramic + activated carbon media developed by KLT Filtration, 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, do not hesitate to contact our customer service by e-mail at the following address: info@pure-filters.com.