The problem
PFAS (per- and polyfluoroalkyl substances) are a large class of synthetic chemicals. Testing usually reports a short list of specific compounds, not the whole class.
The EPA finalized drinking-water limits for several PFAS in 2024. Utilities are on a compliance timeline, so reported data varies.
What public data can and cannot say
Can tell you
- Utility reports and EPA's UCMR 5 dataset show which PFAS were measured in a public system and at what levels.
- The ZIP report summarizes what is public for your serving system.
Cannot tell you
- Public data does not cover private wells.
- A non-detect for the tested compounds does not cover every PFAS compound.
How to test
- Use a lab certified for the PFAS method you need (EPA Method 533 or 537.1).
- Home strips do not measure PFAS.
System types compared
| System type | Format | What to check on the listing | Read |
|---|---|---|---|
| Under-sink RO | Point of use | Whether the seller lists an NSF/ANSI 58 certification that names PFOA/PFOS for that exact model | Reviews |
| Carbon block (under-sink or pitcher) | Point of use | Whether the seller lists NSF/ANSI 53 or 401 scope for PFAS for that exact model | Reviews |
| Whole-house carbon | Point of entry | Listed scope and media replacement interval; drinking-water claims differ from whole-house claims | Reviews |
Under-sink RO
Whether the seller lists an NSF/ANSI 58 certification that names PFOA/PFOS for that exact model
ReviewsCarbon block (under-sink or pitcher)
Whether the seller lists NSF/ANSI 53 or 401 scope for PFAS for that exact model
ReviewsWhole-house carbon
Listed scope and media replacement interval; drinking-water claims differ from whole-house claims
Reviews
Referred equipment
Under-sink RO
Waterdrop G3P800 Tankless RO
Best for: Households comparing tankless RO systems
ReferralEditor's referral. We may earn a commission; the seller fulfills the order. How we make money · Disclosure
Sources
FAQ
- Does HU say a filter removes PFAS?
- No. We quote certifications only as the seller lists them, with the standard name. Check the certifier's own listing for the exact model.
- Can I test for PFAS at home?
- Not with strips. Use a certified lab and ask which compounds and method they report.