CheckPFAS

ZIP Code 91001

High Risk
High Risk PFAS Risk Level

PFAS above EPA limits detected

3 compounds exceed EPA Maximum Contaminant Levels in water serving this ZIP code. Standard pitcher filters like Brita do not remove PFAS. See filter recommendations below.

9
PFAS Detected
3
Above EPA Limits
3
Water Systems
475%
Highest % of MCL

Compounds Exceeding EPA Limits

PFOS Exceeds EPA limit
0 ppt MCL: 4 ppt 475% of limit
Detected: 19.00 ppt
PFOA Exceeds EPA limit
0 ppt MCL: 4 ppt 213% of limit
Detected: 8.50 ppt
PFHxS Exceeds EPA limit
0 ppt MCL: 10 ppt 110% of limit
Detected: 11.00 ppt

What this means for you

One or more PFAS compounds were measured above the EPA's enforceable drinking water limit at a utility serving ZIP 91001. The EPA set these limits because long-term exposure at higher concentrations is associated with health effects including immune suppression, thyroid changes, and cancer risk increases. Standard pitcher filters (Brita, PUR) are not certified to remove PFAS. The most reliable at-home options are under-sink reverse osmosis systems or activated carbon block filters with an NSF/ANSI 58 certification specifically listing PFOA/PFOS reduction. Your water utility is required to bring levels into compliance by 2029 — filtering at the tap is the practical interim step if you'd like additional protection now.

LAS FLORES WATER CO.

CA1910061 Low Level
Water Type
Surface Water
PFAS Detected
1
Above MCL
0
State
California
Data Period
2023–2025

PFAS Test Results

CompoundDetectedvs. EPA LimitEPA LimitStatus
lithium
53600.00pptNo federal limitUnregulated

PASADENA-CITY, WATER DEPT.

CA1910124 Low Level
Water Type
Surface Water
PFAS Detected
1
Above MCL
0
State
California
Data Period
2023–2025

PFAS Test Results

CompoundDetectedvs. EPA LimitEPA LimitStatus
lithium
64200.00pptNo federal limitUnregulated

RUBIO CANON LAND & WATER ASSOCIATION

CA1910140 High Risk
Water Type
Groundwater
PFAS Detected
7
Above MCL
3
State
California
Data Period
2023–2025

PFAS Test Results

CompoundDetectedvs. EPA LimitEPA LimitStatus
PFOS
Perfluorooctane sulfonic acid
19.00ppt
475% of limit
4 ppt⚠ Exceeds MCL
PFOA
Perfluorooctanoic acid
8.50ppt
213% of limit
4 ppt⚠ Exceeds MCL
PFHxS
Perfluorohexane sulfonic acid
11.00ppt
110% of limit
10 ppt⚠ Exceeds MCL
PFBA
Perfluorobutanoic acid
5.70pptNo federal limitUnregulated
PFBS
Perfluorobutane sulfonic acid
3.50pptNo federal limitUnregulated
PFPeA
Perfluoropentanoic acid
3.50pptNo federal limitUnregulated
PFHxA
Perfluorohexanoic acid
3.10pptNo federal limitUnregulated
Note: ZIP code 91001 is served by 3 separate water utilities. Results above show data for each system independently.
About this data
Source
EPA UCMR 5 (Unregulated Contaminant Monitoring Rule, 5th cycle)
Data released
January 2026
Sampling period
January 2023 – December 2025
Systems tested
~10,000 public water systems serving > 25 people
Water systems (PWSID)
CA1910061, CA1910124, CA1910140
Detection threshold (MRL)
~1.5–2 ppt — "Not detected" means below this floor, not zero

Values shown are the highest single-sample concentration measured at entry points to the distribution system. Results reflect water quality at the treatment plant — aging pipes, building plumbing, and on-site storage can affect what actually reaches your tap.