Question 1

What is Perfluoroundecanoic Acid?

Accepted Answer

Perfluoroundecanoic Acid (PFUnA) 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 PFUnA in my drinking water?

Accepted Answer

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

Question 3

What is the EPA limit for PFUnA?

Accepted Answer

Not all PFAS compounds have federal limits yet. The EPA's 2024 PFAS Rule set limits for 6 compounds including PFOA, PFOS, PFHxS, PFNA, and HFPO-DA. Others are still under review.

Question 4

What are the health effects of PFUnA?

Accepted Answer

PFUnA exposure has been linked to: Liver toxicity, Immune system effects, Potential endocrine disruption. Long-term exposure increases risks even at low doses.

Question 5

How do I remove PFUnA from my water?

Accepted Answer

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

Question 6

What is the CAS number for Perfluoroundecanoic Acid?

Accepted Answer

The CAS Registry Number for Perfluoroundecanoic Acid is 2058-94-8.

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