ISO 23956:2022

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 23956
ISO/TC 249
Traditional Chinese medicine —
Secretariat: SAC
Determination of benzopyrene in
Voting begins on:
2021-10-27 processed natural products
Voting terminates on:
2021-12-22
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 23956:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2021

---------------------- Page: 1 ----------------------
ISO/FDIS 23956:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
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
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
  © ISO 2021 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/FDIS 23956:2021(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Test methods . 2
4.1 Reagents and apparatus . 2
4.1.1 Reagents . 2
4.1.2 Apparatus . 2
4.2 Sample preparation . 2
4.3 HPLC-FLD method . 3
4.3.1 Chromatographic condition . 3
4.3.2 Identification . 3
4.3.3 Construction of calibration curve . 3
4.3.4 Quantification . 3
4.4 GC-MS method . 4
4.4.1 Chromatographic conditions . 4
4.4.2 Assay . 4
Annex A (informative) Chemical information of benzopyrene . 6
Annex B (informative) National regulations and limitations of benzopyrene .7
Annex C (informative) The example of HPLC pattern about benzopyrene(s) .8
Annex D (informative) Determination of benzopyrene(s) in wood creosote .9
Bibliography .10
iii
© ISO 2021 – All rights reserved

---------------------- Page: 3 ----------------------
ISO/FDIS 23956:2021(E)
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 of 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
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 249, Traditional Chinese medicine.
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.
iv
  © ISO 2021 – All rights reserved

---------------------- Page: 4 ----------------------
ISO/FDIS 23956:2021(E)
Introduction
The International Agency for Research on Cancer (IARC) classified benzopyrene (C H ) as a carcinogen
20 12
[1]
(Group 1) in 2006. Benzopyrene is produced by the incomplete combustion of carbohydrates, proteins
and fats during high-temperature cooking and processing of raw materials. To prevent hazards induced
by benzopyrene, it is important to determine the benzopyrene content in processed natural products
used in traditional Chinese medicine (e.g. processed Rehmannia root, Cyperus rhizome and mume fruit),
which are processed by the application of high temperatures (200 °C to 600 °C).
Some national pharmacopeias have technical guidelines for the determination of benzopyrene
[2,3]
content . This document describes an analytical method, including the device specifications,
chemical reagents, operation procedures and formulae to determine benzopyrene content, considering
each national pharmacopeia, as well as giving references to other standardized testing methods,
maximum limits and risk assessment.
v
© ISO 2021 – All rights reserved

---------------------- Page: 5 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 23956:2021(E)
Traditional Chinese medicine — Determination of
benzopyrene in processed natural products
1 Scope
This document specifies the method for the determination of benzopyrene content in processed natural
products.
It is applicable to processed natural products such as processed Rehmannia root, processed Cyperus
rhizome, processed ginseng and processed mume fruit. It is not applicable to the analysis of minerals
used in traditional Chinese medicine.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
benzopyrene
C H
20 12
organic compound of pentacyclic hydrocarbons made of pyrene and phenylene group
Note 1 to entry: The chemical information of benzopyrene is described in Annex A. National regulations and
limitations of benzopyrene are given in Annex B.
3.2
polycyclic aromatic hydrocarbon
PAH
compound that contains two or more fused aromatic rings made of only carbon and hydrogen atoms
[SOURCE: ISO 11338-1:2003, 3.3]
3.3
high-performance liquid chromatography
HPLC
technique in analytical chemistry used to separate, identify and quantify each component in a mixture
Note 1 to entry: High-performance liquid chromatography relies on pumps to pass a pressurized liquid solvent
containing the sample mixture through a column filled with a solid adsorbent material. Each component
in the sample interacts differently with the adsorbent material, resulting in different flow rates for different
components, thereby leading to the separation of components as these flow out of the column.
1
© ISO 2021 – All rights reserved

---------------------- Page: 6 ----------------------
ISO/FDIS 23956:2021(E)
3.4
gas chromatography
GC
analytical technique used to separate and determine the components of complex mixtures based on
partitioning between gas and stationary p
...