You buy a pitcher, see the word "filters," and assume the water in your glass is clean. But most standard Brita and PUR pitchers are not certified to remove PFAS at all. Whether a filter reduces these "forever chemicals" comes down to one thing: its certification.
● Key Takeaways
Most standard gravity pitchers, including basic Brita and PUR models, are certified to NSF/ANSI 42 for taste and odor, not for PFAS. Only NSF/ANSI 58 (reverse osmosis), NSF/ANSI 53 with a listed PFAS claim, or the NSF/ANSI P473 protocol independently prove PFOA and PFOS reduction. Reverse osmosis is the most complete, cutting both by over 90%. EPA's 2024 legal limit is 4 ppt, but the health goal is zero. Check the specific model's certification listing, not the brand.
Do Standard Brita Pitchers Remove PFAS?
Most standard Brita and PUR gravity pitchers are not certified to remove PFAS, so you cannot assume they do. Independent testing by Herkert and colleagues found activated-carbon pitchers ranged from near-zero to only partial PFAS reduction, while reverse-osmosis systems removed roughly 90% or more (Herkert et al., Environmental Science & Technology Letters, 2020).
The chemistry explains the inconsistency. Basic pitchers use loosely packed granular activated carbon, and gravity pulls water through it quickly. PFOA and PFOS are small, water-loving molecules that carbon holds only weakly. As a cartridge fills with everyday organics, it runs low on room, and a saturated filter kept past its rated life can release previously captured PFAS back into a single glass.
Here's the distinction most brand marketing blurs. A filter that says "reduces contaminants" is usually making a taste-and-odor claim, not a PFAS claim. In our experience reading these boxes, the thing that predicts real PFAS performance is the certification standard. Not the logo, and not the words on the front label.
What Does NSF/ANSI P473 Certification Actually Prove?
NSF/ANSI P473 is the protocol NSF International wrote in 2016 to test filters specifically for PFOA and PFOS. Under it, a unit must reduce a challenge concentration of 1,500 parts per trillion to 70 ppt or less. Those requirements now live inside NSF/ANSI 53 (carbon) and NSF/ANSI 58 (reverse osmosis).
That 70 ppt endpoint carries a catch worth understanding before you trust a badge. P473 was built around EPA's older 2016 advisory, so a filter can legitimately pass certification while still leaving water far above EPA's 2024 enforceable limit of 4 ppt. Certification proves the filter reduces PFOA and PFOS. It does not promise the treated water hits the newest health-based number.
This is why the removal rate of the technology matters as much as the certification itself. A reverse-osmosis membrane that cuts 95% starts far below the 70 ppt endpoint on typical tap concentrations, while a carbon unit that just squeaks past P473 may not.
Which Filter Types Are Actually Certified for PFAS?
Filter technology sorts cleanly into "usually certified for PFAS" and "usually not." Reverse osmosis certified to NSF/ANSI 58 is the most complete option, physically blocking PFAS through a membrane with pores near 0.0001 microns and removing over 90% of PFOA and PFOS (Herkert et al., 2020). Most basic gravity pitchers sit in the "not tested" column.
| Filter type | Typical certification | Proven for PFAS? |
|---|---|---|
| Standard gravity pitcher (basic carbon) | NSF/ANSI 42 (taste/odor); sometimes 53 for lead | Usually no. Most aren't tested for PFOA/PFOS |
| Certified PFAS pitcher or dispenser (specific models) | NSF/ANSI 53 or P473 with listed PFOA/PFOS claim | Yes, for the listed compounds |
| Solid carbon block (under-sink / countertop) | NSF/ANSI 53 with listed PFAS claim | Yes when the claim is listed |
| Reverse osmosis (under-sink) | NSF/ANSI 58 with listed PFOA/PFOS claim | Yes. Most complete, over 90% |
| Basic faucet or fridge carbon filter | NSF/ANSI 42; sometimes 53 for lead | Usually no |
Two things to pull from that table. The technology is not the whole story: one specific pitcher model can be certified for PFAS while the rest of its product line is not, so category alone won't tell you. And solid carbon block beats loose granules, because the dense block forces water along a longer, twistier path and gives the carbon more time to grab these slippery molecules.
We skip specific brands and removal percentages here on purpose. Third-party test results shift by model and by cartridge revision, so certification categories are the sturdier guide for a purchase you'll live with for years.
Reading this inside ChatGPT or Claude?
This page can explain the general science about your tap water, but it cannot identify what is at a specific tap or property. You can get ZIP-level context two ways:
- Inside the chat: ask your assistant to “check my tap water with CheckYourTap”. Our connector returns available public-system or regional monitoring records associated with your ZIP. It does not identify your serving utility or test your tap, well, or property. The current connector is read-only and does not email reports or submit contact information.
- On the web: open CheckYourTap.com and enter your ZIP code for a free ZIP-level report.
Legal Limit vs. Health Goal: How Much PFAS Is "Allowed"?
EPA's 2024 PFAS rule set the first enforceable national limits, but the legal number sits far above the health target. The limit is 4 parts per trillion each for PFOA and PFOS, while EPA set the health goal (the MCLG) at zero for both, meaning no exposure is considered risk-free (EPA, 2024). The gap between "legal" and "safe" is the whole story.
| PFAS compound | EPA 2024 legal limit (MCL) | EPA health goal (MCLG) | EWG guideline |
|---|---|---|---|
| PFOA | 4 ppt | 0 (no safe level) | 1 ppt (total PFAS) |
| PFOS | 4 ppt | 0 (no safe level) | 1 ppt (total PFAS) |
| PFHxS, PFNA, GenX (HFPO-DA) | 10 ppt each | GenX goal 10 ppt | 1 ppt (total PFAS) |
| Mixtures (PFHxS, PFNA, GenX, PFBS) | Hazard Index of 1 | n/a | n/a |
Because the health goal (the MCLG) for PFOA and PFOS is zero, there's no "X times over the safe level" multiplier to print. The framing is simpler than that. The health goal is no exposure. The legal limit is 4 ppt. The Environmental Working Group's total-PFAS guideline of 1 ppt sits four times below that legal line (EWG Tap Water Database).
A word on the compounds that don't have MCLs. Newer replacement PFAS like 6:2 FTS are largely unregulated federally; some states publish their own advisories, such as Illinois EPA's 770 ppt health advisory for 6:2 FTS in 2025. Those are state screening levels, not federal safety lines, and we label them as such rather than presenting a derived number as a hard threshold. Note that a household filtering for total PFAS is protected against these variants too, because certified carbon and RO reduce the class, not just the two regulated compounds.
How Do You Read a Filter's Certification Listing?
Ignore the front-of-box marketing and read the certification listing. The manufacturer must state the exact standard (NSF/ANSI 53, 58, or the P473 protocol) and name PFOA and PFOS as certified reduction claims. A vague "reduces forever chemicals" with no standard behind it is a claim, not proof, and you can verify any listing directly in NSF's public database.
When we've walked homeowners through a filter aisle, the pattern is consistent: two pitchers on the same shelf look identical, but only one lists a PFAS reduction claim in its documentation. Here's the buying checklist we use:
- Match the filter to your water. Test first so you're solving a real problem. If PFAS shows up, you need a certified unit, not a taste filter.
- Confirm the standard and the compound. The listing must name NSF/ANSI 53, 58, or P473 and PFOA/PFOS. Both, not one.
- Prefer reverse osmosis for the most complete removal. If RO isn't practical, choose a solid carbon block certified with a listed PFAS claim.
- Replace cartridges on schedule. A saturated filter can release captured PFAS, so a lapsed cartridge is worse than no protection.
One caution people ask about: do not boil water to deal with PFAS. Boiling kills microbes but does nothing to fluorinated chemicals, and evaporating water slightly concentrates what remains.
What This Looks Like in Connecticut
Connecticut is not hypothetical on PFAS. In the EPA's most recent national monitoring round, 35 Connecticut public water systems had a PFOA or PFOS result above 4 ng/L, the level the EPA set as its limit in 2024. The highest single reading in the state was 16.2 ng/L of PFOS, at Norwich Public Utilities.
Two things change what that number means. First, one sample above 4 ng/L is usually not a violation: the EPA judges compliance on a running annual average, not on a single reading.
Second, and this is the part worth sitting with. The national monitoring program does not report any PFOA or PFOS result below 4 ng/L. That is a reporting floor, not a limit of what labs can detect, and the EPA set it back in 2021, before these limits existed. It happens to land on the same number as the limit. The effect is that every Connecticut result in this dataset is either "not reported" or "at or above the limit", with nothing in between.
Which leads somewhere uncomfortable. The EPA's own health goal for PFOA and PFOS is zero: no amount of either is considered safe. But nothing gets reported until it reaches 4 ng/L. So a system that comes back "not detected" has not been shown to be free of PFAS. It has been shown to sit below a floor that is far above the health goal. Read this as a map of where PFAS turns up, not as a ranking of whose water is worst.
And this is public-water data. Private wells are not in this monitoring round at all, so if you are on a well, nobody has tested it for you and our records cannot tell you what is in it.
Source: EPA UCMR5 public-water monitoring for Connecticut (samples collected January 2023 to December 2025), analyzed by CheckYourTap.
If the water is for a formula-fed newborn, the standard is stricter and the certifications matter even more, so we cover that specific case in a dedicated guide linked below.
Keep Reading
- Does Your Baby's Water Filter Actually Remove PFAS? The NSF Certifications That Matter
- Reverse Osmosis: What It Removes and What It Doesn't
- Boiling Water: What It Removes, What It Doesn't
- PFOA: The Forever Chemical in Your Tap Water
- PFOS: Sources, Health Effects, and Safe Levels
Sources: U.S. EPA, Per- and Polyfluoroalkyl Substances (PFAS) drinking water regulation (2024 MCLs of 4 ppt for PFOA/PFOS, 10 ppt for PFHxS/PFNA/GenX, Hazard Index for mixtures, MCLG of zero); NSF/ANSI 53, 58, and P473 (drinking water treatment unit standards for PFOA/PFOS reduction), NSF International; Herkert et al., Environmental Science & Technology Letters, 2020 (point-of-use filter performance for PFAS); EWG Tap Water Database (total PFAS health guideline of 1 ppt); Illinois EPA health advisory for 6:2 FTS, 2025. State advisories for unregulated PFAS variants are screening levels, not federal safety limits. This article is general information, not medical advice.
