Perfluoroundecanoic Acid (PFUnA)

Perfluoroundecanoic acid (PFUnA), also called PFUnDA or C11, is an 11-carbon PFAS compound that is monitored under UCMR5 testing. It is primarily found as an impurity in fluoropolymer production processes. PFUnA tends to accumulate in animal tissues and has been found in fish, wildlife, and humans. Its longer chain length means it has a higher tendency for bioaccumulation compared to PFOA. No federal drinking water limit exists, but it is part of the monitoring framework to better characterize PFAS contamination in US water systems.