Skip to content
Well & TapHome Water Treatment Database

Is there PFAS in City of Fullerton water?

Yes. EPA's final UCMR 5 results show City of Fullerton averaged 13.3 ppt of PFOS at its worst sampling point, 3.3 times the EPA limit of 4 ppt.

City of Fullerton Serves 139,461 people · 17 PFOA samples from 7 sampling points · Mar 2023 to Apr 2026 Average above an EPA limit
PFOA Perfluorooctanoic acid 10.8 ppt avg
EPA 4
PFOS Perfluorooctanesulfonic acid 13.3 ppt avg
EPA 4
PFHxS Perfluorohexanesulfonic acid 6.2 ppt avg
EPA 10
Hazard index GenX, PFBS, PFNA, PFHxS combined 0.6 avg
EPA 1

Also detected, no federal limit: PFPeA, PFHxA, PFBS, PFBA, PFHpA.

Averages are for the worst sampling point, with non-detects counted as zero. Source: EPA UCMR 5.

City of Fullerton is a public water system drawing on surface water, based in Fullerton, California, serving about 139,461 people. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 17 times across 7 sampling points between Mar 2023 and Apr 2026.

Every PFAS detected

PFAS Detected Highest Worst point avg EPA limit
PFOS
Perfluorooctanesulfonic acid
3 of 17 13.3 ppt 13.3 ppt 4 ppt
PFPeA
Perfluoropentanoic acid
4 of 17 13.2 ppt 12.9 ppt none
PFHxA
Perfluorohexanoic acid
4 of 17 12.4 ppt 11.8 ppt none
PFOA
Perfluorooctanoic acid
3 of 17 10.8 ppt 10.8 ppt 4 ppt
PFBS
Perfluorobutanesulfonic acid
3 of 17 7.6 ppt 7.2 ppt none
PFHxS
Perfluorohexanesulfonic acid
3 of 17 6.2 ppt 6.2 ppt 10 ppt
PFBA
Perfluorobutanoic acid
3 of 17 5.9 ppt 5.9 ppt none
PFHpA
Perfluoroheptanoic acid
3 of 17 4.8 ppt 4.5 ppt none

Not detected: 11Cl-PF3OUdS, PFUnA, PFDoA, PFDA, PFNA, 9Cl-PF3ONS, PFMBA, ADONA, HFPO-DA, 6:2 FTS, 4:2 FTS, 8:2 FTS, PFPeS, PFEESA, NFDHA, PFMPA, NMeFOSAA, PFTA, PFTrDA, NEtFOSAA, PFHpS.

Lithium, tested in the same program: highest 35.5 ppb, detected in 7 of 16 samples. EPA's health-based screening level is 10 ppb.

What the EPA limits mean here

In April 2024 EPA set enforceable limits of 4 ppt for PFOA and PFOS, 10 ppt each for PFHxS, PFNA and GenX, and a hazard index of 1 for mixtures. Utilities were given until 2029 to comply. In May 2026 EPA proposed keeping only the PFOA and PFOS limits and moving that deadline to 2031. Until that proposal is final, the 2024 limits stand.

Compliance is judged on a running annual average at each entry point, so we show the average at this system's worst sampling point next to its single highest result. UCMR 5 results do not by themselves put a utility in or out of compliance.

What you can do at home

Two routes work for PFAS. For drinking and cooking water only, a reverse osmosis system certified to NSF/ANSI 58 with a PFOA/PFOS reduction claim is the cheapest proven option. To treat every tap and shower, a whole-house carbon system with enough contact time works, but check that the maker has PFAS test data, not just a marketing claim. See the best filters for PFAS and how PFAS removal works.

Other systems in California

All 707 tested systems in California

ZIP codes served

92831 92832 92833 92835

As reported by the utility to EPA. Neighbouring ZIPs are often split between systems; your water bill names yours.

Cite this page

Well & Tap. "PFAS in City of Fullerton water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID CA3010010. https://wellandtap.com/pfas/california/city-of-fullerton/

About this data

Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID CA3010010). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.