Unbranded countertop water-filtration unit beside a glass carafe and tumbler in a sunlit kitchen.

Does Clearly Filtered Remove Microplastics? What One Home Test Found

A household screening test counted 14 suspected microplastic particles before a Clearly Filtered under-sink system was installed and 1 afterward. The drop is encouraging, but this was one small home test, not a certified removal study.

Quick answer

A Mamavation test reported 14 suspected particles in 100 mL of unfiltered tap water and 1 after installing a Clearly Filtered 3-Stage Under the Sink system. A separate sample from the brand's refrigerator filter had 3.

The under-sink count fell by about 93%, but that should not be treated as a proven removal rate. The test could not confirm which particles were plastic, did not measure nanoplastics, included no sample-specific blank and was not publicly repeated. We did not find a current microplastics certification for either exact model.

What did the test find?

Mamavation partnered with The Water Map to test two products:

  • Unfiltered kitchen faucet: 14 suspected particles
  • Clearly Filtered under-sink system: 1 suspected particle
  • Clearly Filtered refrigerator filter: 3 suspected particles

The under-sink comparison is the stronger of the two because it includes a before-and-after count from the kitchen faucet. Mamavation did not publish a clearly paired unfiltered baseline for the refrigerator result, so we would not turn its count of 3 into a removal percentage.

The difference between 14 and 1 is large enough to be interesting. It suggests the under-sink system may have reduced the larger particles detected by this screening method in that home. It does not tell us how consistently the system would perform in other homes or as its cartridges age.

Why these are "suspected" particles

The test used Nile Red, a fluorescent dye that binds to water-repelling surfaces. Many common plastics will glow after staining, but some waxes, oils, rubber fragments and organic material can glow too. Confirming that a particle is plastic requires laboratory methods such as FTIR or Raman spectroscopy.

The Water Test describes its kit as a screening tool rather than a laboratory analysis. Each sample contains about 100 mL. Its filter can retain particles down to roughly 1 micrometer, but the included microscope reliably counts particles at about 10 micrometers and larger. Nanoplastics below 1 micrometer are outside its range.

There was also no procedural blank run alongside these samples. The kit developer says its own clean-water blanks have produced 0 to 3 particles. That means the filtered counts of 1 and 3 are low, but they are also within the method's stated background range.

The useful signal here is the difference between the unfiltered and filtered samples. The exact low counts should not be read as proof that only one or three plastic particles remained.

Was this independent testing?

The testing appears to have been conducted separately from Clearly Filtered's manufacturer performance testing, but the coverage is not commercially neutral.

Mamavation discloses that Clearly Filtered has been one of its largest sponsors for years and has sponsored some of its PFAS testing. The article also contains affiliate links and a discount code. The Water Test offers a separate Mamavation partnership package.

Those relationships do not make the result false. They do mean readers should see this as a commercially connected, affiliate-supported product story rather than neutral product validation.

Are the filters certified for microplastics?

We did not find a current model-specific microplastics certification for the tested CF-UTSF under-sink cartridges or CF-INLINE refrigerator filter.

Clearly Filtered says those products were tested by QFT, now part of IAPMO New Jersey, against a long list of contaminants. Their published performance pages do not include a microplastics row for either model.

The brand publishes a separate >99.99% microplastics result for its CF-PRF pitcher filter. That is a different product and test, so the percentage should not be transferred to the under-sink or refrigerator systems.

The current NSF listing we found for the Clearly Filtered pitcher covers chlorine reduction and taste and odor under NSF/ANSI 42, plus lead-content requirements under NSF/ANSI/CAN 372. It does not list a certified microplastics claim. Clearly Filtered says it is pursuing additional certification under NSF/ANSI 53 and 401.

This distinction matters. Testing by an accredited laboratory can provide useful evidence. Certification goes further by tying a specific model and claim to a public listing, manufacturing oversight and periodic retesting.

Would PFK recommend either filter from this result?

Not yet. One before-and-after screen is a good reason to investigate further, not enough for a product recommendation.

We would want to see repeated paired samples, a blank processed alongside them, details about cartridge age and flushing, and a model-specific test or certification covering a defined particle-size range. Testing later in the cartridge's rated life would be especially useful.

Neither product is plastic-free, either. Clearly Filtered describes the systems as using BPA- and BPS-free medical-grade materials. Reducing particles in the water and removing plastic from the entire water-contact path are different goals.

For choosing a filter today, start with your local water report and look for an exact model with verified claims for the contaminants you need to reduce. Our guide to filtering microplastics from drinking water explains what to check.

PFK assessment: The 14-to-1 result is an encouraging household observation. It supports taking a closer look at Clearly Filtered, but it does not establish a certified removal percentage or answer the harder questions about smaller particles, cartridge life and repeatability.

Sources

Research reviewed September 30, 2026. This article analyzes one household screening comparison. It is not a product recommendation or a guarantee of drinking-water safety.

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