Introduction

In the European Union, several groups of per- and polyfluoroalkyl substances (PFAS) are restricted whether on their own, in mixtures or in articles.

Regulation (EU) 2019/1021 on persistent organic pollutants (POPs) [1] restricts:

— perfluorooctane sulfonic acid and its derivatives (PFOS);
— perfluorooctanoic acid (PFOA), its salts and PFOA-related compounds;
— perfluorohexane sulfonic acid (PFHxS), its salts and PFHxS-related compounds (status September 2024).

Regulation (EC) No 1907/2006 (REACH), Annex XVII, Entry 68 [2] restricts:

— perfluorocarboxylic acids containing 9 to 14 carbon atoms in the chain (C9-C14 PFCAs), their salts and C9-C14 PFCA-related substances;
— perfluorohexanoic acid (PFHxA), its salts and PFHxA-related substances, in textiles in clothing and related accessories for the general public from 10 October 2026, in textiles other than in clothing and related accessories for the general public from 10 October 2027 [3] (status September 2024).

Restrictions of other groups of PFAS are subject to the REACH restriction process [4].

Additionally, several per- and poly-fluorinated alkyl substances (PFAS), which are not restricted under the EU-POPs or EU-REACH regulations have been added as substances of very high concern (SVHC) to the candidate list according to Regulation (EC) No 1907/2006 (REACH), Article 59 [2].

Some of the aforementioned restrictions can also concern side-chain fluorinated polymers if they are PFOA or C9-C14 PFCA-related substances. By using methanol as extraction solvent as described in EN 17681‑1:2022 and EN 17681‑2:2022, the presence of side-chain fluorinated polymers cannot be determined.

This document describes a method that will result in alkaline hydrolysis of certain side-chain fluorinated polymers during the extraction process by using a mixture of methanol and aqueous sodium hydroxide solution as extraction solvent. This extraction solvent cannot only extract residual PFAS from the sample, but also cleaves the polymers that are esters of polymerized hydrocarbon acids, such as acrylic acid, and n:2 fluorotelomer alcohols (n:2 FTOHs) to release n:2 FTOHs as a consequence. By quantifying the amount of n:2 FTOHs, one can indirectly assess whether the amount of side-chain fluorinated polymers consisting of polymerised hydrocarbon acids and n:2 FTOHs exceeds the limits for polymers that are related substances to perfluorocarboxylic acids, which are restricted under the relevant EU-POPs or EU-REACH regulations.

Since the group of PFAS consist of several thousand substances it is not possible to test for all of them in targeted testing, e.g. for many PFAS reference standards are not available. Therefore, CEN/TC 248/WG 26 “Textiles — Test methods for analysis of EC restricted substances”, CEN/TC 289/WG 1 “Chemical test methods”, CEN/TC 309/WG 2 “Footwear and environmental aspects“ and ISO/TC 216/WG 2 “Chemical Test methods for footwear and footwear components” formed a joint working group which discussed which PFAS are likely to be found in textiles, textile products, leather and footwear materials. Based on test results and experiences provided by experts of the joined working group, the group agreed on the PFAS listed in Table 2 as lead substances which are recommended to be tested in order to significantly minimize the risk of PFAS contaminations in textiles, textile products, leather and footwear materials. Furthermore, it was considered to only include PFAS for which analytical reference standards were available. In addition, Table 1 was added to provide background information which categories of PFAS exist and for which purpose particular groups of PFAS are or were used.

WARNING — The use of this document involves hazardous materials. It does not purport to address all of the safety or environmental problems associated with its use. It is the responsibility of users of this document to take appropriate measures to ensure the safety and health of personnel and the environment prior to application of the document and fulfil statutory and regulatory requirements for this purpose.

Table 1 — Examples of subgroups of PFAS and their applications

Subgroups of PFAS	Applications
Subgroups of PFAS	Use	Sources of contamination a
K⁺, Li⁺, diethanolamine (DEA) salt	Surfactant for alkaline cleaners	Surfactant in fire-fighting foam, emulsifier in floor polish, mist suppressant for metal plating baths, surfactant for etching acids for circuit boards, pesticide active ingredient for ant bait traps
Amines	—	Mist suppressant for metal plating baths
Ammonium salts	—	Emulsifier for fluoropolymer production
Amphoterics	Water/solvent repellence for leather/paper	—
Carboxylates	—	Antistatic agent in photographic paper
Amides	—	Pesticide active ingredient
Oxazolidinones	—	Waterproofing casts (electronics)
Alcohols, silanes, alkoxylates, fatty acid esters, adipates, urethanes, polyurethanes polyesters, acrylates, polyacrylates	Soil and water repellence	—
Copolymers, phosphate esters	Water repellence	Soil, oil and water repellence for plates, food containers, bags, wraps, folding cartons, containers, carbonless forms, masking papers

a These substances are not relevant in the manufacturing process of textiles, but it is possible to find them as contaminants.

Table 2 — PFAS regulated in the EU and considered for regulation1

No.	Substance		CAS Registry Number® (CAS RN®) a	Applicable chromatographic system		EU regulation ¹
No.	Substance		CAS Registry Number® (CAS RN®) a	Liquid chromatography	Gas chromatography see informative Annex F	EU regulation ¹
C4-C5 Perfluoro carboxylic acids
1	PFBA	Perfluoro-n-butanoic acid	375–22–4	X	—	Included in a proposal to amend REACH Annex XVII
2	PFPeA	Perfluoro-n-pentanoic acid	2706–90–3	X	—	Included in a proposal to amend REACH Annex XVII
C4-C5 Perfluoro carboxylic acids related substances
3	4:2 FTOH	4:2 Fluorotelomer alcohol	2043–47–2	X	—	Included in a proposal to amend REACH Annex XVII
Perfluoro hexanoic acid and salts b
4	PFHxA	Perfluoro-n-hexanoic acid	307–24–4	X	—	REACH Annex XVIIj
4.1b	APFHx	Perfluoro-n-hexanoic acid salts				REACH Annex XVIIj
4.1b	APFHx	‒ Ammonium perfluoro-n-hexanoate	21615–47–4	X	—	REACH Annex XVIIj
Perfluoro hexanoic acid related substances c
5	6:2 FTOH	6:2 Fluorotelomer alcohol	647–42–7	X	—	REACH Annex XVIIj
6f	6:2 FTA	6:2 Fluorotelomer acrylate	17527–29–6	—	X	REACH Annex XVIIj
7f	6:2 FTMA	6:2 Fluorotelomer methacrylate	2144–53–8	—	X	REACH Annex XVIIj
8	6:2 FTS	6:2 Fluorotelomer sulfonic acid	27619–97–2	X	—	REACH Annex XVIIj
Perfluoro heptanoic acids
9	PFHpA	Perfluoro-n-heptanoic acid	375–85–9	X	—	REACH (SVHC)
10	7HPFHpA	7H-Perfluoroheptanoic acid	1546–95–8	X	—	Included in a proposal to amend REACH Annex XVII
Perfluoro octanoic acid and salts b
11	PFOA	Perfluoro-n-octanoic acid	335–67–1	X	—	POPs and REACH (SVHC)
11.1b		Perfluoro-n-octanoic acid salts		X	—	POPs
	APFO	‒ Ammonium perfluoro-n-octanoate	3825–26–1
	Na-PFO	‒ Sodium perfluoro-n-octanoate	335–95–5
	K-PFO	‒ Potassium perfluoro-n-octanoate	2395–00–8
	Ag-PFO	‒ Silver perfluoro-n-octanoate	335–93–3
Perfluoro octanoic acid related substances c
12e	F-PFO	Perfluoro-n-octanoyl fluoride	335–66–0	X	—	POPs
13e	Me-PFOA	Methyl perfluoro-n-octanoate	376–27–2	—	X	POPs
14e	Et-PFOA	Ethyl perfluoro-n-octanoate	3108–24–5	—	X	POPs
15g	8:2 FTOH	8:2 Fluorotelomer alcohol	678–39–7	X	—	POPs and REACH Annex XVII
16f	8:2 FTA	8:2 Fluorotelomer acrylate	27905–45–9	—	X	POPs
17f	8:2 FTMA	8:2 Fluorotelomer methacrylate	1996–88–9	—	X	POPs
18	8:2 FTS	8:2 Fluorotelomer sulfonic acid	39108–34–4	X	—	POPs
C9-C14 Perfluoro carboxylic acids and salts c
19	PFNA	Perfluoro-n-nonanoic acid	375–95–1	X	—	REACH Annex XVII and SVHC
19.1b		Perfluoro-n-nonanoic acid salts				REACH Annex XVII and SVHC
19.1b	Na-PFN	‒ Sodium perfluoro-n-nonanoate	21049–39–8	X	—	REACH Annex XVII and SVHC
20	PFDA	Perfluoro-n-decanoic acid	335–76–2	X	—	REACH Annex XVII and SVHC
20.1b		Perfluoro-n-decanoic acid salts				REACH Annex XVII and SVHC
	NH4-PFD	‒ Ammonium perfluoro-n-decanoate	3108–42–7	X	—
	Na-PFD	‒ Sodium perfluoro-n-decanoate	3830–45–3	X	—
21	PFUnA	Perfluoro-n-undecanoic acid	2058–94–8	X	—	REACH Annex XVII and SVHC
22	PFDoA	Perfluoro-n-dodecanoic acid	307–55–1	X	—	REACH Annex XVII and SVHC
23	PFTrDA	Perfluoro-n-tridecanoic acid	72629–94–8	X	—	REACH Annex XVII and SVHC
24	PFTeDA	Perfluoro-n-tetradecanoic acid	376–06–7	X	—	REACH Annex XVII and SVHC
25	PF-3,7-DMOA	Perfluoro(3,7-dimethyloctanoic acid)	172155–07–6	X	—	REACH Annex XVII
C9-C14 Perfluoro carboxylic acids related substances c
26	4HPFUnA	2H,2H,3H,3H-Perfluoro-n-undecanoic acid	34598–33–9	X	—	REACH Annex XVII
15g	8:2 FTOH	8:2 Fluorotelomer alcohol	678–39–7	X	—	POPs and REACH Annex XVII
27	10:2 FTOH	10:2 Fluorotelomer alcohol	865–86–1	X	—	REACH Annex XVII
28f	10:2 FTA	10:2 Fluorotelomer acrylate	17741–60–5	—	X	REACH Annex XVII
29f	10:2 FTMA	10:2 Fluorotelomer methacrylate	2144–54–9	—	X	REACH Annex XVII
30	10:2 FTS	10:2 Fluorotelomer sulfonic acid	120226–60–0	X	—	REACH Annex XVII
Perfluoro octane sulfonic acid and its salts d
31	PFOS	Perfluoro-n-octane sulfonic acid	1763–23–1	X	—	POPs
31.1b	PFOS-X	Perfluoro-n-octane sulfonic acid salts C₈F₁₇SO₂X		X	—	POPs
		‒ Potassium perfluoro-n-octane sulfonate	2795–39–3
		‒ Lithium perfluoro-n-octane sulfonate	29457–72–5
		‒ Ammonium perfluoro-n-octane sulfonate	29081–56–9
		‒ Bis(2-hydroxyethyl)ammonium perfluoro-n-octane sulfonate	70225–14–8
		‒ Tetraethyl ammonium perfluoro-n-octane sulfonate	56773–42–3
		‒ Didecyl(dimethyl) azanium perfluoro-n-octane sulfonate	251099–16–8
Perfluoro octane sulfonic acid derivates d
32	FOSA	Perfluoro-1-octanesulfonamide	754–91–6	X	—	POPs
33	N-MeFOSA	N-Methylperfluoro-1-octanesulfonamide	31506–32–8	X	—	POPs
34	N-EtFOSA	N-Ethylperfluoro-1-octanesulfonamide	4151–50–2	X	—	POPs
35	N-MeFOSE	2-(N-Methylperfluoro-1-octanesulfonamido)-ethanol	24448–09–7	X	—	POPs
36	N-EtFOSE	2-(N-Ethylperfluoro-1-octanesulfonamido)-ethanol	1691–99–2	X	—	POPs
37h	PFOSF	Perfluoro-1-octanesulfonyl fluoride	307–35–7	X	—	POPs
Perfluoro sulfonic acids and its salts b
38	PFBS	Perfluorobutanesulfonic acid	375–73–5	X	—	REACH (SVHC)
39	PFHxS	Perfluoro-n-hexanesulfonic acid	355–46–4	X	—	POPs
40	PFHpS	Perfluoro-n-heptanesulfonic acid	375–92–8	X	—	Included in a proposal to amend REACH Annex XVII
41	PFDS	Perfluoro-n-decanesulfonic acid	335–77–3	X	—	Included in a proposal to amend REACH Annex XVII
42	4:2 FTS	4:2 Fluorotelomer sulfonic acid	757124–72–4	X	—	Included in a proposal to amend REACH Annex XVII
Perfluoro-2-propoxypropanoic acid its salts b and derivatives
43	HFPO-DA	Perfluoro-2-propoxypropanoic acid	13252–13–6	X	—	REACH (SVHC)
43.1	HFPO-DA-X	Perfluoro-2-propoxypropanoic acid salts and acyl halides				REACH (SVHC)
		X = Fi	2062–98–8	X	—
		X = NH₄b	62037–80–3	X	—
		X = Kb	67118–55–2	X	—

a CAS Registry Number® (CAS RN®) is a trademark of the American Chemical Society (ACS). This information is given for the convenience of users of this document and does not constitute an endorsement by CEN of the product named. Equivalent products may be used if they can be shown to lead to the same results.

b Salts cannot be identified by the method described in this document and only be quantified as the corresponding acid.

c If required legally or as agreed with the customer the results of related substances shall be summed up (9.3).

d If required legally or as agreed with the customer the results of PFOS and its derivates shall be summed up and calculated as PFOS (9.3).

e Substance is hydrolysed and releases PFOA when treated with methanol/sodium hydroxide solution (8.4). It contributes to the amount of PFOA if present in the sample.

f Substance is hydrolysed and releases related fluorotelomer alcohols (n:2 FTOH) when treated with methanol/sodium hydroxide solution (8.4). It contributes to the amount of the related n:2 FTOH if present in the sample.

g 8:2 FTOH can degrade to PFOA and is thus a PFOA-related substance [7]. It contains a C₈F₁₇C-moiety which is also characterized as a C9-C14 PFCA-related substance [5].

h Substance will convert to PFOS.

i Substance is hydrolysed and can only be quantified as HFPO-DA.

j Coming into force for textiles in clothing and related accessories for the general public from 10 October 2026, for textiles other than in clothing and related accessories for the general public from 10 October 2027 [3].

BS EN 17681-1:2025

Textiles and textile products. Per- and polyfluoroalkyl substances (PFAS) - Analysis of an alkaline extract using liquid chromatography and tandem mass spectrometry

Current

Published:

31 May 2025