Not on the chart: San Bernardino’s PFOS result was below the lab’s reporting limit, so it can’t be placed among the cities that detected it.
In California, 113 of 398 city reports had a PFAS sample above a 2024 EPA limit. PFAS across California →
Your tap usually reflects the system’s water, but results vary between samples and sources. Only a certified lab test tells you what reaches your glass today.
How to test for PFASPFAS are measured in parts per trillion. Home strips can’t read that low, so a certified lab is the only way to get a number for your tap.
These are the methods behind the federal results. Ask which compounds are on the panel, so PFHxS, PFBS and PFHxA are included, and keep the reporting limit with your result.
Find a certified lab in California ↗ (opens in a new tab)No home strip has been shown to detect PFAS at the levels federal limits use. A mail-in lab kit is the closest at-home option; check that its lab is accredited and that its panel names the compounds you need.
Read your lab results →Why: these are the technologies certified to reduce PFAS. Certification is compound by compound, so check that a listing names the compound you need to reduce.
★ Best available: Aquasana Claryum 3-Stage Max Flow Under-Sink Filter (AQ-6300M), the best fit here; nothing in this group is certified yet.
| Pick | Product | Details and price | Certification | Why it’s listed | Link |
|---|---|---|---|---|---|
| ★ Best available | Under-sinkAquasana Claryum 3-Stage Max Flow Under-Sink Filter (AQ-6300M) | Price$$ | Not certified for Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA), PFHxS and Perfluoropentanoic acid (PFPeA) | See the evidence | Check price at Aquasana |
| Also good | CountertopAquasana Clean Water Machine Countertop Filter (AQ-CWM2) | Price$$ | Not certified for Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA), PFHxS and Perfluoropentanoic acid (PFPeA) | See the evidence | Check price at Aquasana |
| Also good | Reverse osmosisSmartFlow® Reverse Osmosis | TechnologyReverse osmosisPrice$$$ | Not certified for Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA), PFHxS and Perfluoropentanoic acid (PFPeA) | See the evidence | Check price at Aquasana |
★ Best choice: HealthShield™, certified for PFHxS.
| Pick | Product | Details and price | Certification | Why it’s listed | Link |
|---|---|---|---|---|---|
| ★ Best choice | Whole-houseHealthShield™ | TreatsPFHxSPrice$$$$ | Certified for PFHxS (NSF/ANSI 53, WQA) | Why it’s listed: its current certification names PFHxS, found in San Bernardino’s record.See the evidence | Check price at Aquasana |
| $ Budget pick | Whole-houseiSpring WGB32B-PFKS PFAS & Heavy Metals Whole House FilterUse code REFISPRING at checkout: 10% off your first iSpring order. | Price$$$ | Brand lab-tested for PFAS, not independently certified for Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA), PFHxS and Perfluoropentanoic acid (PFPeA) | See the evidence | Check price at iSpring |
Looking for regulated PFAS? Filters certified for PFOA and PFOS →
Also: hard water picks →
PurityMap earns a commission from these links. "Best choice" and "Budget pick" go to certified products first; commission never decides them. Affiliate disclosure.
PFHxS was detected below its federal limit; a system result is not your tap result. The 25 compounds not detected were below the lab’s reporting limit, which is not the same as zero. And 29 compounds were tested; PFAS not on that list have no result here.
Four PFAS were detected; none is above a federal limit. In EPA UCMR 5 testing of SAN BERNARDINO CITY (2024-04-17 to 2024-10-17): PFHxS 4 ng/L (limit 10), PFBS 4.4 ng/L (EPA health advisory 2,000), PFHxA 4 ng/L (state limit 400,000), PFPeA 3.4 ng/L (no federal or state limit) and the other 25 PFAS tested not detected. "Not detected" means below the lab's reporting limit, not proven zero.
EPA's 2024 drinking-water rule set maximum contaminant levels of 4.0 ng/L for PFOA and for PFOS, and 10 ng/L for PFHxS, PFNA and HFPO-DA (GenX). In May 2026 EPA proposed keeping the PFOA and PFOS limits, with the option of until 2031 to comply, and rescinding the other three. Until a final rule, all five limits apply. The 2024 rule also set a Hazard Index of 1 for mixtures of two or more of PFHxS, PFNA, GenX and PFBS; EPA has proposed rescinding it, and it applies until a final rule.
No. They have no federal drinking-water limit (MCL); the 2024 rule sets limits only for PFOA, PFOS, PFHxS, PFNA and HFPO-DA (GenX). PFBS has no limit of its own; the 2024 rule counts it only inside the Hazard Index for mixtures, which EPA has proposed rescinding. PFBS has an EPA health advisory of 2,000 ng/L, a screening level, not a legal limit. PFHxA has a 400,000 ng/L state limit. San Bernardino's results: PFBS 4.4 ng/L, PFHxA 4 ng/L and PFPeA 3.4 ng/L.
No. "Not detected" (ND) means the result was below the lab's reporting limit, not that the compound is absent. In San Bernardino's record, 25 of the 29 PFAS tested were not detected. Their reporting limits run from 2 to 20 ng/L.
29 PFAS compounds in EPA UCMR 5 testing of SAN BERNARDINO CITY (2024-04-17 to 2024-10-17), including the five with federal limits. PFHxS, PFBS, PFHxA and PFPeA were detected. PFAS not on that list have no result here.
Yes. These results describe the water system as a whole, and levels vary between samples and sources over time. PFAS come with the water rather than from home plumbing, so your tap usually reflects the system's water, but only a certified lab test of your own tap gives a number for your glass.
Use a state-certified lab that runs EPA Method 533 or 537.1, the methods behind the federal results. Ask which compounds are on the panel, so PFHxS, PFBS and PFHxA are included, and keep the reporting limit with your result. No home test strip has been shown to detect PFAS at the levels federal limits use.
Reverse osmosis, activated carbon and anion exchange can reduce PFAS, but certification is compound by compound. Look for NSF/ANSI 53 or 58 naming the compound; RO systems often carry it under 53. Choose a model whose current listing names the compound you need to reduce, here PFHxS, PFBS and PFHxA, check it in the certifier's listing (NSF, WQA or IAPMO), and replace cartridges on schedule.
Look for PFHxS, PFBS and PFHxA by name in the certifier's listing (NSF, WQA or IAPMO) for the exact model: NSF/ANSI 53 and 58 listings name each PFAS a filter was tested to reduce. A listing for PFOA and PFOS alone does not cover PFHxS, PFBS and PFHxA.
Compliance with the 2024 limits is judged on a running annual average, with a compliance date of 2029 (EPA has proposed allowing until 2031 for PFOA and PFOS). EPA has proposed rescinding the PFHxS, PFNA, GenX and Hazard Index limits; they apply until a final rule.