Is There PFAS in Rosemont Tap Water?
Rosemont, CA: PFOS 13.4 ng/L, 3× EPA's 4 ng/L limit; PFOA and PFHxS also above. Every PFAS result and filter certifications per compound.
7 of 29 PFAS detected
Each result is read against its own reference. Only PFHxS, PFOA and PFOS have federal limits. PFBA, PFHpA and PFPeA have no federal or state limit and are shown for transparency, not graded.
- PFOSFederal MCLPerfluorooctanesulfonic acid13.4ng/LAbove its limit · sampled 2023-03-13 to 2024-11-12Evidence
- PFOAFederal MCLPerfluorooctanoic acid8.2ng/LAbove its limit · sampled 2023-03-13 to 2024-11-12Evidence
- PFHxSFederal MCLPerfluorohexanesulfonic acid10.9ng/LAbove its limit · limit under EPA review · sampled 2023-03-13 to 2024-11-12Evidence
- PFHxAState MCL · MichiganPerfluorohexanoic acid5.4ng/LDetected, below its state limit · sampled 2023-03-13 to 2024-11-12Evidence
- PFBANo limitPerfluorobutanoic acid9ng/L
No federal or state limit: shown for transparency, not graded.
Detected, no limit · sampled 2023-03-13 to 2024-11-12Evidence - PFPeANo limitPerfluoropentanoic acid7.7ng/L
No federal or state limit: shown for transparency, not graded.
Detected, no limit · sampled 2023-03-13 to 2024-11-12Evidence - PFHpANo limitPerfluoroheptanoic acid4.7ng/L
No federal or state limit: shown for transparency, not graded.
Detected, no limit · sampled 2023-03-13 to 2024-11-12Evidence
- PFOAMCL8.2 ng/L
- PFOSMCL13.4 ng/L
- PFHxSMCL10.9 ng/L
- PFNAMCLNot detected
- HFPO-DA (GenX)MCLNot detected
- PFHxA5.4 ng/L
- PFBA9 ng/L
- PFHpA4.7 ng/L
- PFPeA7.7 ng/L
- 11Cl-PF3OUdSNot detected
- 4:2 FTSNot detected
- 6:2 FTSNot detected
- 8:2 FTSNot detected
- 9Cl-PF3ONSNot detected
- ADONANot detected
- NEtFOSAANot detected
- NFDHANot detected
- NMeFOSAANot detected
- PFBSNot detected
- PFDANot detected
- PFDoANot detected
- PFEESANot detected
- PFHpSNot detected
- PFMBANot detected
- PFMPANot detected
- PFPeSNot detected
- PFTANot detected
- PFTrDANot detected
- PFUnANot detected
MCL marks the 5 PFAS given a federal limit in EPA's 2024 rule. EPA has proposed rescinding three of those limits; they apply until a final rule.
Results as a table29 results with limit, status, sample date and source
| Contaminant | Result | Limit | Status | Sampled | Source |
|---|---|---|---|---|---|
| Perfluorooctanesulfonic acid (PFOS) | 13.4 ng/L | 4.0 ng/L federal MCL (2024) | Above a historical reference; current applicability unverified | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluorooctanoic acid (PFOA) | 8.2 ng/L | 4.0 ng/L federal MCL (2024) | Above a historical reference; current applicability unverified | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluorohexanesulfonic acid (PFHxS) | 10.9 ng/L | 10 ng/L federal MCL (2024) | Above a historical reference; current applicability unverified | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluorohexanoic acid (PFHxA) | 5.4 ng/L | 400,000 ng/L Michigan EGLE state MCL (strictest US state) | Within a historical reference; current applicability unverified | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluorobutanoic acid (PFBA) | 9 ng/L | No federal or state limit; shown for transparency | Detected, no limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluoroheptanoic acid (PFHpA) | 4.7 ng/L | No federal or state limit; shown for transparency | Detected, no limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluoropentanoic acid (PFPeA) | 7.7 ng/L | No federal or state limit; shown for transparency | Detected, no limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) | < 2 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals) | < 5 ng/L | 10 ng/L federal MCL (2024) | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA) | < 5 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA) | < 6 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Nonafluoro-3,6-dioxaheptanoic acid (NFDHA) | < 20 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluoro-3-methoxypropanoic acid (PFMPA) | < 4 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluoro-4-methoxybutanoic acid (PFMBA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluorobutanesulfonic acid (PFBS) | < 3 ng/L | 2,000 ng/L EPA health advisory (screening, not a legal limit)Screening level, not a legal limit | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluorodecanoic acid (PFDA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluorododecanoic acid (PFDoA) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluoroheptanesulfonic acid (PFHpS) | < 3 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluorononanoic acid (PFNA) | < 4 ng/L | 10 ng/L federal MCL (2024) | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluoropentanesulfonic acid (PFPeS) | < 4 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluorotetradecanoic acid (PFTA) | < 8 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluorotridecanoic acid (PFTrDA) | < 7 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
| Perfluoroundecanoic acid (PFUnA) | < 2 ng/L | No federal or state limit; shown for transparency | Not detected above the reporting limit | 2023-03-13 to 2024-11-12 | UCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010) |
PFOS across 764 cities with a detected value
3,396 more were below the lab's 4 ng/L reporting limit and aren't plotted, and 34 have no result on record. 66 cities above 25 ng/L are grouped in the last bar. A position here is not a verdict on the water.
have a regulated PFAS above the federal limit.
PFAS across California →- CAL AM - SUBURBAN ROSEMONT's water system as a whole, as reported to EPA UCMR 5.
- 29 PFAS compounds, each with its own result.
- Samples taken 2023-03-13 to 2024-11-12.
- The water at your tap. Building plumbing isn't in this record.
- PFAS not listed in the 29 above were not reported in these records.
- Levels since the last sample have not been published.
Test first, then match a certified method.
A tap test can confirm levels at your home before you choose treatment.
- PFHxS · exceeds the limit
- PFOA · exceeds the limit
- PFOS · exceeds the limit
- PFHxA · detected below the limit
- PFBA · detected, no federal or state limit
- PFHpA · detected, no federal or state limit
- PFPeA · detected, no federal or state limit
- Reverse osmosisOpen the method →
- Activated carbon (GAC)Open the method →
- Anion exchangeOpen the method →
Fit for Rosemont’s PFAS, compound by compound
Each filter is checked against the 7 PFAS detected here. A ✓ needs a current certification record that names the compound. A PFAS claim on the box is not enough.
As an Amazon Associate, PurityMap earns from qualifying purchases. A product appears here only when a current certification record covers at least one identified concern; every concern stays listed. The retail offer is looked up afterwards and never changes which products appear or their order. Affiliate disclosure.
- ✓Certified for this compound
- ?Claimed or likely, not established
- –No claim on record

Aquasana Claryum 2-Stage Under-Sink Filter (AQ-5200)
Activated Carbon (Claryum)- PFHxS10.9 ng/L–No claim on record
- PFOA8.2 ng/L✓Certified for this compound
- PFOS13.4 ng/L✓Certified for this compound
- PFHxA5.4 ng/L–No claim on record
- PFBA9 ng/L–No claim on record
- PFHpA4.7 ng/L–No claim on record
- PFPeA7.7 ng/L–No claim on record
Certified for PFOA, PFOS; not established for PFHxS, PFHxA, PFBA, PFHpA, PFPeA.

Aquasana Claryum 3-Stage Max Flow Under-Sink Filter (AQ-6300M)
Activated Carbon (Claryum)- PFHxS10.9 ng/L–No claim on record
- PFOA8.2 ng/L✓Certified for this compound
- PFOS13.4 ng/L✓Certified for this compound
- PFHxA5.4 ng/L–No claim on record
- PFBA9 ng/L–No claim on record
- PFHpA4.7 ng/L–No claim on record
- PFPeA7.7 ng/L–No claim on record
Certified for PFOA, PFOS; not established for PFHxS, PFHxA, PFBA, PFHpA, PFPeA.

Aquasana Clean Water Machine Countertop Filter (AQ-CWM2)
Activated Carbon (Claryum)- PFHxS10.9 ng/L–No claim on record
- PFOA8.2 ng/L✓Certified for this compound
- PFOS13.4 ng/L✓Certified for this compound
- PFHxA5.4 ng/L–No claim on record
- PFBA9 ng/L–No claim on record
- PFHpA4.7 ng/L–No claim on record
- PFPeA7.7 ng/L–No claim on record
Certified for PFOA, PFOS; not established for PFHxS, PFHxA, PFBA, PFHpA, PFPeA.

Patriot Pure Ultimate Water Filtration System
Gravity pour-through (Nanomesh filter)- PFHxS10.9 ng/L–No claim on record
- PFOA8.2 ng/L✓Certified for this compound
- PFOS13.4 ng/L✓Certified for this compound
- PFHxA5.4 ng/L–No claim on record
- PFBA9 ng/L–No claim on record
- PFHpA4.7 ng/L–No claim on record
- PFPeA7.7 ng/L–No claim on record
Certified for PFOA, PFOS; not established for PFHxS, PFHxA, PFBA, PFHpA, PFPeA.

AquaTru Carafe Countertop Reverse-Osmosis Purifier (AT100)
Reverse Osmosis- PFHxS10.9 ng/L–No claim on record
- PFOA8.2 ng/L✓Certified for this compound
- PFOS13.4 ng/L✓Certified for this compound
- PFHxA5.4 ng/L–No claim on record
- PFBA9 ng/L–No claim on record
- PFHpA4.7 ng/L–No claim on record
- PFPeA7.7 ng/L–No claim on record
Certified for PFOA, PFOS; not established for PFHxS, PFHxA, PFBA, PFHpA, PFPeA.

AquaTru Classic Countertop Reverse-Osmosis Purifier (AT2000)
Reverse Osmosis- PFHxS10.9 ng/L–No claim on record
- PFOA8.2 ng/L✓Certified for this compound
- PFOS13.4 ng/L✓Certified for this compound
- PFHxA5.4 ng/L–No claim on record
- PFBA9 ng/L–No claim on record
- PFHpA4.7 ng/L–No claim on record
- PFPeA7.7 ng/L–No claim on record
Certified for PFOA, PFOS; not established for PFHxS, PFHxA, PFBA, PFHpA, PFPeA.

Waterdrop G3P600 Tankless Reverse-Osmosis System
Reverse Osmosis- PFHxS10.9 ng/L–No claim on record
- PFOA8.2 ng/L✓Certified for this compound
- PFOS13.4 ng/L✓Certified for this compound
- PFHxA5.4 ng/L–No claim on record
- PFBA9 ng/L–No claim on record
- PFHpA4.7 ng/L–No claim on record
- PFPeA7.7 ng/L–No claim on record
Certified for PFOA, PFOS; not established for PFHxS, PFHxA, PFBA, PFHpA, PFPeA.

Waterdrop G3P800 Tankless Reverse-Osmosis System
Reverse Osmosis- PFHxS10.9 ng/L–No claim on record
- PFOA8.2 ng/L✓Certified for this compound
- PFOS13.4 ng/L✓Certified for this compound
- PFHxA5.4 ng/L–No claim on record
- PFBA9 ng/L–No claim on record
- PFHpA4.7 ng/L–No claim on record
- PFPeA7.7 ng/L–No claim on record
Certified for PFOA, PFOS; not established for PFHxS, PFHxA, PFBA, PFHpA, PFPeA.

Whirlpool Filter 3 Refrigerator Water Filter (WHR3RXD1)
Activated Carbon- PFHxS10.9 ng/L–No claim on record
- PFOA8.2 ng/L✓Certified for this compound
- PFOS13.4 ng/L✓Certified for this compound
- PFHxA5.4 ng/L–No claim on record
- PFBA9 ng/L–No claim on record
- PFHpA4.7 ng/L–No claim on record
- PFPeA7.7 ng/L–No claim on record
Certified for PFOA, PFOS; not established for PFHxS, PFHxA, PFBA, PFHpA, PFPeA.
- Browse, not a match:
- Brita Elite Water Filter Pitcher
- Clearly Filtered Pitcher (lab-tested, not NSF 53 certified)
- Culligan ZeroWater 10-Cup Pitcher (ZEROP10)
- Frizzlife SP99 Under-Sink Filter
Frequently asked
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Is there PFAS in Rosemont tap water?
In EPA's UCMR 5 testing of CAL AM - SUBURBAN ROSEMONT (2023-03-13 to 2024-11-12): PFBA 9 ng/L (no federal or state limit), PFHpA 4.7 ng/L (no federal or state limit), PFHxA 5.4 ng/L (state limit 400,000), PFHxS 10.9 ng/L (limit 10), PFOA 8.2 ng/L (limit 4), PFOS 13.4 ng/L (limit 4), PFPeA 7.7 ng/L (no federal or state limit) and the other 22 PFAS tested not detected. "Not detected" means below the lab's reporting limit, not proven zero.
What are the federal PFAS limits?
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. Results above them today are above the limits in force.
How do I remove PFAS from my tap water?
Reverse-osmosis systems and filters certified to NSF/ANSI 53 or 58 for PFOA/PFOS reduction are the proven options at the tap. Check the certifier's listing (NSF, WQA or IAPMO) for the exact model, and replace cartridges on schedule.
- UCMR5 Analytical ResultsUCMR5 Analytical Results: CAL AM - SUBURBAN ROSEMONT (CA3410010)US EPA · 2026-01-15View source ↗
- State SDWIS Compliance RecordLead & Copper Rule 90th-percentile: CAL AM - SUBURBAN ROSEMONT (CA3410010)US EPA SDWIS · 2026-07-09View source ↗