ISO/DIS 21084

ISO/TC 38

Secretariat: JISC

Date: 2025-12-08

Textiles — Method for determination of alkylphenols (AP)

This draft is submitted to a parallel vote in ISO, CEN.

Textiles — Méthode de détermination de la teneur en alkylphénols (AP)

This draft is submitted to a parallel vote in ISO, CEN.

DIS stage

© ISO 2025

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of the requester.

ISO copyright office

CP 401 • Ch. de Blandonnet 8

CH-1214 Vernier, Geneva

Phone: + 41 22 749 01 11

E-mail: copyright@iso.org

Website: www.iso.org

Published in Switzerland

Contents

Foreword iv

1 Scope 1

2 Normative references 1

3 Terms and definitions 1

4 Principle 1

5 Reagents 1

6 Apparatus 2

6.1 General 2

6.2 Apparatus and auxiliaries for preparing the sample 2

6.3 Chromatographic equipment 2

7 Procedure 2

7.1 Standard preparation 2

7.2 Sample preparation 2

7.3 Sample extraction 2

7.4 Sample analysis 3

8 Calculation and calibration 3

8.1 Calibration curve 3

8.2 External calibration 3

8.3 Calculation of each AP in sample 3

8.4 Reliability of the method 3

9 Test report 4

Annex A (informative) Examples of chromatographic condition — GC-MS/MS 5

Annex B (informative) Examples of chromatographic condition — LC-MS/MS and LC-FLD 8

Annex C (informative) Reliability of the method 10

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.

For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISO's adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 38, Textiles.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Textiles — Method for determination of alkylphenols (AP)

WARNING — This document calls for the use of substances/procedures that may be injurious to the health/environment if appropriate conditions are not observed. It refers only to technical suitability and does not absolve the user from legal obligations relating to health and safety/environment at any stage.

This document specifies the method for the determination of extractable alkylphenols (AP) without derivatization step in textile and textile products.

There are no normative references in this document.

No terms and definitions are listed in this document.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

• ISO Online browsing platform: available at https://www.iso.org/obp
• IEC Electropedia: available at http://www.electropedia.org/

The test specimen is cut into small pieces, transferred to a sample vial and treated with methanol in ultrasonic water bath. The extract is filtered and collected. Subsequently, the collected extract is analysed by gas chromatograph with mass selective detector (GC-MS), liquid chromatograph with mass selective detector (LC-MS) or liquid chromatograph with fluorescence detector (LC-FLD).

Unless otherwise specified, analytical grade chemicals shall be used.

4-n-Octylphenol, CAS No.1806-26-4.

4-tert-Octylphenol, CAS No.140-66-9.

4-n-Nonylphenol, CAS No.104-40-5.

4-Nonylphenol, CAS No. 84852-15-3.

Methanol, (HPLC grade).

Acetonitrile, (HPLC grade).

Water, (HPLC grade).

Glassware shall be free of analytes (alkylphenols).

Standard laboratory equipment and the following.

Balance with resolution of 0,01 g (for test specimen preparation).

Analytical balance with resolution of 0,001 g (for standard preparation).

Glass vial with screw cap (e.g. 40 ml).

Ultrasonic water bath [to be set up at (70 ± 5) °C].

Disposable syringe and membrane filter (with pore size of 0,45 μm or less).

Glass vial with septum cap (for chromatographic instrument).

Gas chromatograph with mass selective detector (GC-MS), or

Liquid chromatograph with mass selective detector (LC-MS), or

Liquid chromatograph with fluorescence detector (LC-FLD).

Capillary column for gas chromatograph.

C18 reverse phase column for liquid chromatograph.

Octylphenols and nonylphenols are weighed accurately with analytical balance (6.2.3) and dissolved with methanol (5.5) containing 1 000 mg/l for stock solution. The stock solution can be preserved in the dark at less than 4°C.

NOTE Commercial standard solutions are available.

The test specimen is cut into pieces with 5 mm × 5 mm and pieces are mixed homogeneously. The specimen is weighed 1 g to the nearest 0,01 g with balance (6.2.2) and put into the 40 ml glass vial (6.2.4) for extraction.

10 ml of methanol (5.5) are added to glass vial (6.2.4) for extraction. If sample is not sufficiently immersed in the extraction solvent, add more methanol and record the final volume for calculation of each AP described in 8.3. Then the sample vial is sonicated for extraction in ultrasonic water bath (6.2.5) at (70 ± 5) °C for (60 ± 5) min. Subsequently, the extract is cooled down to room temperature, approximately 1 ml to 2 ml of extract is filtered into sample vial (6.2.7) using disposable syringe equipped with membrane filter (6.2.6). The sample vial is closed with cap immediately for further analysis.

In general, samples are examined without concentration, but the instrumental equipment of the laboratories may vary, the concentration procedure of extract is applicable for lower detection limit.

Qualitative and quantitative analysis of alkylphenols is performed by using GC-MS, LC-MS or LC-FLD.

Guidelines for suitable chromatographic conditions are given in Annex A for GC-MS/MS and in Annex B for LC-MS/MS and LC-FLD.

In case of positive results using GC-MS method, the results shall be confirmed using LC techniques.

NOTE False-positive results using GC-MS method could be caused by decomposition of tris(nonylphenyl)phosphate (TNPP) due to high injection temperature.

Prepare a calibration curve of the response against the known standard concentration with at least three calibration points. From the calibration curve, the concentration of the AP (alkylphenols; octylphenols and nonylphenols) in mg/l (C_S) is determined.

NOTE Concentration ranges for the calibration standards are subject to change upon the need of each laboratory and equipment used.

The concentration of each AP in sample extract solution is calculated in mg/l according to Formula (1):

(1)

where

C_S is the concentration of each AP in sample extract solution, in μg/ml;

C_C is the concentration of each AP in calibration solution, in mg/l;

A_S is the area response of each AP in sample extract solution;

A_C is the area response of each AP in calibration solution.

The AP level is calculated as mass portion, X_i, in mg/kg of the specimen according to Formula (2):

(2)

where

X_i is the concentration of each AP in sample, in mg/kg;

C_S is the concentration of each AP and calculated according to Formula (1), in µg/ml;

V is the final volume of extract solution, in ml;

m is the mass of test specimen, in g;

DF is the dilution factor.

The reliability of the method is given in Annex C.

The test report shall include the following information:

1. a reference to this document, i.e. ISO 21084:2019;
2. identification of sample and the date of analysis;
3. detection method and quantification method;
4. the result of each AP (nonylphenols and octylphenols are reported individually);
5. details of any deviation from the procedure specified and of all circumstances that may have influenced the results.
6. 
   (informative)
   
   Examples of chromatographic condition — GC-MS/MS
   1. Preliminary remark

As the instrumental equipment of the laboratories may vary, no generally applicable instructions can be provided for chromatographic analyses. The following parameters have been successfully tested and used.

• 1. Gas chromatographic conditions
     1. GC-MS/MS condition

Capillary column: (5 %-phenyl)-methylpolysiloxane phase, length 35 m, inside diameter 0,25 mm, film thickness 0,25 μm

Injector mode: Splitless

Injector temperature: 250 °C

Injection volume: 1 μl

Carrier gas: Helium (rate: 1,0 ml/min)

Collision gas: Nitrogen (rate: 1,5 ml/min)

Oven program: 80 °C (0 min), 80 °C to 230 °C (7 °C/min), 230 °C (2 min)

Detection: Tandem mass spectrometer (MS/MS)

Acquisition mode: MRM mode, see Table A.1 for MRM condition.

Table A.1 — MRM condition in GC-MS/MS

See examples in Figure A.1 and Figure A.2.

Key

1 4-tert-Octylphenol

2 4-Nonylphenol

3 4-n-Octylphenol

4 4-n-Nonylphenol

X retention time, min

Y abundance

Figure A.1 — Total ion chromatogram (TIC) of alkylphenols in GC-MS/MS

Key

X retention time, min

Y abundance

TIC total ion chromatogram

Figure A.2 — MRM chromatogram of 4-nonylphenol (technical mixture) in GC-MS/MS

1. 
   (informative)
   
   Examples of chromatographic condition — LC-MS/MS and LC-FLD
   1. Liquid chromatographic conditions

Mobile phase 1: Acetonitrile (ACN)

Mobile phase 2: Water

Column: C18 (2,1 × 100 mm, 1,8 μm, pore size 95 Å)

Column temperature: 40 °C

Flow rate: 0,3 ml/min

Injection volume: 5 μl

Mobile phase condition: 0 min to 12 min 65 % ACN, 12 min to 18 min 98 % ACN

Table B.1 — Mobile phase condition

• 1. Detector conditions
     1. Tandem mass spectrometer (MS/MS)

Ionization mode: API-ES

Polarity: Negative

Desolvation temperature: 350 °C

Desolvation gas flow (N₂): 11 l/min

Nebulizer: 50 psi

Sheath gas flow rate: 12 l/min

Sheath gas temperature: 350 °C

Capillary voltage: 3 500 V

Nozzle voltage: 1 000 V

Acquisition mode: MRM mode, see Table B.2 for MRM condition.

Table B.2 — MRM condition in LC-MS/MS

• • 1. Fluorescence detector (FLD)

Wavelength: 230 nm for excitation and 296 nm for emission

See example in Figure B.1.

Key

1 4-tert-Octylphenol

2 4-Nonylphenol

3 4-n-Octylphenol

4 4-n-Nonylphenol

X retention time, min

Y abundance

Figure B.1 — Chromatogram of alkylphenols in LC-FLD

1. 
   (informative)
   
   Reliability of the method

The following statistical data presented in Table C.1, Table C.2, Table C.3 have been obtained for AP content in 3 kinds of samples through an interlaboratory test with 9 participating laboratories.

Table C.1 — Statistical data of the interlaboratory test (textile sample)

Table C.2 — Statistical data of the interlaboratory test (solution sample with low concentration)

Table C.3 — Statistical data of the interlaboratory test (solution sample with high concentration)