EPA legal limit
10 ppt
Maximum Contaminant Level
EWG health guideline
0.004 ppt
Science-based, stricter target
Health effects
Associated with thyroid disruption, immune effects, and reproductive harm. Classified by IARC as possibly carcinogenic.
Where it comes from
Industrial discharge, food packaging, and firefighting foam. Found at elevated levels near fluorochemical manufacturing facilities.
How it's regulated
Regulated under EPA 2024 PFAS rule as part of the hazard index with PFHxS, HFPO-DA, and PFBS.
The EPA vs EWG gap
The legal limit (10 ppt) is 2500× higher than the EWG health guideline (0.004 ppt). Water can be legally compliant while still exceeding the science-based threshold.
How to filter pfna
Not all filters address pfna. Look for independently certified filters — NSF International certification means the removal claim has been independently verified.
Frequently asked questions
What is pfna?
A long-chain PFAS compound used in food packaging, carpets, and industrial coatings. Less common than PFOA and PFOS but found in some U.S. water supplies.
What are the health effects of pfna?
Associated with thyroid disruption, immune effects, and reproductive harm. Classified by IARC as possibly carcinogenic.
Is pfna regulated in drinking water?
Regulated under EPA 2024 PFAS rule as part of the hazard index with PFHxS, HFPO-DA, and PFBS.
Where does pfna come from?
Industrial discharge, food packaging, and firefighting foam. Found at elevated levels near fluorochemical manufacturing facilities.
How do I remove pfna from tap water?
The most effective methods for removing pfna are: Reverse osmosis (RO), NSF 58 certified RO system. Look for NSF-certified systems — independent certification confirms removal claims have been verified.
Is pfna in your water?
Enter your ZIP code to see the measured level in your specific utility.