Question 1

What is Perfluorononanoic Acid?

Accepted Answer

Perfluorononanoic Acid (PFNA) is a per- and polyfluoroalkyl substance (PFAS) – a synthetic chemical used in manufacturing, firefighting foam, and consumer products. It persists indefinitely in water and the human body.

Question 2

Is PFNA in my drinking water?

Accepted Answer

EPA UCMR5 testing (2023-2025) monitors PFNA at 6,800+ US water systems. Enter your ZIP code at KnowYourExposure.com to see if PFNA has been detected in your specific utility.

Question 3

What is the EPA limit for PFNA?

Accepted Answer

The EPA drinking water limit for PFNA is 10 parts per trillion (ppt). Utilities have until 2029 to reduce levels below this threshold under the 2024 PFAS Rule.

Question 4

What are the health effects of PFNA?

Accepted Answer

PFNA exposure has been linked to: Thyroid disease, Immune suppression, Reproductive harm. Long-term exposure increases risks even at low doses.

Question 5

How do I remove PFNA from my water?

Accepted Answer

Certified reverse osmosis systems remove 90%+ of most PFAS including PFNA. Activated carbon and ion exchange filters also work. Boiling does NOT remove PFAS – it concentrates them.

Question 6

What is the CAS number for Perfluorononanoic Acid?

Accepted Answer

The CAS Registry Number for Perfluorononanoic Acid is 375-95-1.

PFNA: Health Effects, EPA Limits & Sources (2026)