CheckPFAS

ZIP Code 77521

High Risk
High Risk PFAS Risk Level

PFAS above EPA limits detected

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

17
PFAS Detected
1
Above EPA Limits
4
Water Systems
150%
Highest % of MCL

Compounds Exceeding EPA Limits

PFOS Exceeds EPA limit
0 ppt MCL: 4 ppt 150% of limit
Detected: 6.00 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 77521. 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.

CITY OF MONT BELVIEU

TX0360017 Low Level
Water Type
Groundwater
PFAS Detected
1
Above MCL
0
State
Texas
Data Period
2023–2025

PFAS Test Results

CompoundDetectedvs. EPA LimitEPA LimitStatus
lithium
26700.00pptNo federal limitUnregulated

CITY OF BAYTOWN

TX1010003 High Risk
Water Type
Surface Water
PFAS Detected
8
Above MCL
1
State
Texas
Data Period
2023–2025

PFAS Test Results

CompoundDetectedvs. EPA LimitEPA LimitStatus
PFOS
Perfluorooctane sulfonic acid
6.00ppt
150% of limit
4 ppt⚠ Exceeds MCL
PFHxS
Perfluorohexane sulfonic acid
5.10ppt
51% of limit
10 pptBelow limit
lithium
13800.00pptNo federal limitUnregulated
PFBA
Perfluorobutanoic acid
14.60pptNo federal limitUnregulated
PFPeA
Perfluoropentanoic acid
10.20pptNo federal limitUnregulated
PFHxA
Perfluorohexanoic acid
9.80pptNo federal limitUnregulated
PFBS
Perfluorobutane sulfonic acid
5.70pptNo federal limitUnregulated
PFHpA
Perfluoroheptanoic acid
3.70pptNo federal limitUnregulated

LAKE MUD

TX1011741 Low Level
Water Type
Surface Water
PFAS Detected
4
Above MCL
0
State
Texas
Data Period
2023–2025

PFAS Test Results

CompoundDetectedvs. EPA LimitEPA LimitStatus
PFBA
Perfluorobutanoic acid
7.30pptNo federal limitUnregulated
PFPeA
Perfluoropentanoic acid
5.00pptNo federal limitUnregulated
PFHxA
Perfluorohexanoic acid
4.80pptNo federal limitUnregulated
PFBS
Perfluorobutane sulfonic acid
3.30pptNo federal limitUnregulated

SPRING MEADOWS MUD

TX1013261 Low Level
Water Type
Surface Water
PFAS Detected
4
Above MCL
0
State
Texas
Data Period
2023–2025

PFAS Test Results

CompoundDetectedvs. EPA LimitEPA LimitStatus
PFBA
Perfluorobutanoic acid
7.20pptNo federal limitUnregulated
PFHxA
Perfluorohexanoic acid
4.90pptNo federal limitUnregulated
PFPeA
Perfluoropentanoic acid
4.90pptNo federal limitUnregulated
PFBS
Perfluorobutane sulfonic acid
3.10pptNo federal limitUnregulated
Note: ZIP code 77521 is served by 4 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)
TX0360017, TX1010003, TX1011741, TX1013261
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.