At a glance
| Chemical family | PFAS — perfluoroalkyl sulfonamide (PFOS precursor, metabolises to PFOS in body and environment) |
| CAS number | 754-91-6 |
| Classification | Not individually IARC classified. Transforms to PFOS (a persistent organic pollutant under Stockholm Convention). PFOA classified IARC Group 1 (2023). PFOSA is a PFOS precursor — its toxicity is mediated through PFOS formation |
| Where you encounter it | Legacy Scotchgard-treated textiles and carpets; stain-resistant fabric treatments; house dust from treated products; food packaging (legacy); some firefighting foams |
| Sleep micro-environment relevance | Found in house dust from legacy Scotchgard-treated upholstery, carpets, and textiles. Transforms to PFOS in the body. Persistent in the environment and in household dust |
Regulatory & certification status
| European Union | PFOS and its precursors (including PFOSA) are restricted under the EU POPs Regulation (Regulation 2019/1021). PFOS listed as a POP under the Stockholm Convention since 2009. Regulatory |
| United States | 3M voluntarily phased out PFOS and precursors by 2002. EPA Significant New Use Rule (SNUR) requires EPA review before PFOS/PFOSA can be manufactured or imported. Not individually listed under SDWA. Regulatory |
| Canada | PFOS and its precursors restricted under CEPA. Prohibited Substances List. Regulatory |
| International | PFOS and precursors listed as POPs under the Stockholm Convention (2009). PFOA classified IARC Group 1 (2023). PFOSA not individually IARC classified. Global phase-out of PFOS chemistry largely complete. Regulatory |
What it is
PFOSA is a perfluorooctane sulfonamide — a neutral PFAS compound that serves as a precursor to PFOS. When PFOSA is absorbed into the body (through dust ingestion, dermal contact, or inhalation), it is biotransformed by liver enzymes to PFOS, which is extremely persistent (biological half-life of 4-6 years in humans). PFOSA was a key intermediate in 3M's electrochemical fluorination process and was present in Scotchgard products and other PFOS-based surface treatments. 3M voluntarily phased out PFOS and PFOS-precursor chemistry in 2000-2002 after the discovery of widespread environmental and human contamination. PFOS is listed as a persistent organic pollutant under the Stockholm Convention (2009). PFOSA persists in legacy-treated products — furniture, carpets, and textiles treated before the phase-out continue to release PFOSA into house dust.
Where it shows up in bedding
PFOSA enters the bedroom through legacy fabric treatments: furniture, carpets, mattress protectors, and curtains that were treated with Scotchgard or similar PFOS-based stain-resistant products before the 2002 phase-out continue to release PFOSA into house dust. PFOSA is semi-volatile and partitions between air and dust. It has been detected in house dust in homes with older treated textiles. During sleep, exposure occurs through dust ingestion and dermal contact. After absorption, PFOSA transforms to PFOS, which accumulates in blood with a half-life of years. Newer stain-resistant treatments use shorter-chain PFAS or non-fluorinated alternatives, but legacy products can persist in homes for decades.
Citations
- Stockholm Convention. PFOS listing — Decision SC-4/17 (2009). Source Regulatory
- Olsen, G.W. et al. (2007). Half-Life of Serum Elimination of Perfluorooctanesulfonate, Perfluorohexanesulfonate, and Perfluorooctanoate in Retired Fluorochemical Production Workers. Environmental Health Perspectives, 115(9): 1298-1305. Source Peer-reviewed
- EPA. PFOS, PFOA, and Other PFAS — Basic Information. Source Regulatory
Frequently asked questions
Can old Scotchgard-treated furniture still release PFOSA?
Yes. Furniture, carpets, and textiles treated with Scotchgard or other PFOS-based products before the 2002 phase-out can continue to release PFOSA into house dust for decades. PFAS are called 'forever chemicals' because they do not break down under normal environmental conditions. If your upholstered furniture or carpet was manufactured before approximately 2005 and was stain-protected, it likely contains PFOS-based chemistry.
What happens to PFOSA in the body?
After absorption, PFOSA is biotransformed by liver enzymes to PFOS (perfluorooctane sulfonate). PFOS is extremely persistent in the body — it has a biological half-life of approximately 4-6 years. It accumulates in blood and liver. PFOS has been associated with immunotoxicity, thyroid disruption, liver effects, and developmental outcomes in epidemiological studies. This is why PFOSA exposure is of concern: the end product is PFOS.
Related compounds
Embr is a sleep environment company researching and addressing the chemistry of the bedroom. Research and product development in progress.
Last reviewed 2026-07-08. If you find a factual error, contact us.