pfasUCMR5Unregulated by EPA

PFDoA (perfluorododecanoic acid)

Reviewed for accuracy against EPA data and peer-reviewed literature · Updated May 2026

PFDoA is a twelve-carbon long-chain carboxylic acid PFAS. Its long chain makes it among the most bioaccumulative PFAS compounds, concentrating in blood, liver, and kidney tissue. Detected in UCMR5 monitoring at relatively low frequencies but of high concern when found due to its persistence in the body.

CAS 307-55-1

EPA legal limit

No federal limit

Maximum Contaminant Level

EWG health guideline

0.5 ppt

Science-based, stricter target

Health effects

PFDoA has an estimated biological half-life exceeding ten years. Animal studies demonstrate liver toxicity, reproductive harm, immune suppression, and developmental effects. Its long chain results in greater bioaccumulation than PFOA (eight-carbon), raising concern at lower detected concentrations.

Where it comes from

Legacy use in industrial fluorochemical processes. Found near fluoropolymer manufacturing sites and in water contaminated by PFAS-containing industrial waste. Less prevalent in drinking water than PFOA and PFOS but detected across multiple states in UCMR5.

How it's regulated

No federal EPA MCL. Not individually regulated under the 2024 PFAS NPDWR. Monitored under UCMR5. EWG health guideline: 0.5 ppt, reflecting the high bioaccumulation potential of very long-chain PFAS.

How to filter pfdoa

Not all filters address pfdoa. Look for independently certified filters—NSF International certification means the removal claim has been independently verified.

Reverse osmosis (RO)NSF 58
NSF 58 certified RO system

Frequently asked questions

What is pfdoa?

PFDoA is a twelve-carbon long-chain carboxylic acid PFAS. Its long chain makes it among the most bioaccumulative PFAS compounds, concentrating in blood, liver, and kidney tissue. Detected in UCMR5 monitoring at relatively low frequencies but of high concern when found due to its persistence in the body.

What are the health effects of pfdoa?

PFDoA has an estimated biological half-life exceeding ten years. Animal studies demonstrate liver toxicity, reproductive harm, immune suppression, and developmental effects. Its long chain results in greater bioaccumulation than PFOA (eight-carbon), raising concern at lower detected concentrations.

Is pfdoa regulated in drinking water?

No federal EPA MCL. Not individually regulated under the 2024 PFAS NPDWR. Monitored under UCMR5. EWG health guideline: 0.5 ppt, reflecting the high bioaccumulation potential of very long-chain PFAS.

Where does pfdoa come from?

Legacy use in industrial fluorochemical processes. Found near fluoropolymer manufacturing sites and in water contaminated by PFAS-containing industrial waste. Less prevalent in drinking water than PFOA and PFOS but detected across multiple states in UCMR5.

How do I remove pfdoa from tap water?

The most effective methods for removing pfdoa are: Reverse osmosis (RO), NSF 58 certified RO system. Look for NSF-certified systems—independent certification confirms removal claims have been verified.

Is pfdoa in your water?

Enter your ZIP code to see the measured level in your specific utility.