SIST EN ISO 21268-4:2020
(Main)Soil quality - Leaching procedures for subsequent chemical and ecotoxicological testing of soil and soil-like materials - Part 4: Influence of pH on leaching with initial acid/base addition (ISO 21268-4:2019)
Soil quality - Leaching procedures for subsequent chemical and ecotoxicological testing of soil and soil-like materials - Part 4: Influence of pH on leaching with initial acid/base addition (ISO 21268-4:2019)
This document specifies a test to obtain information on the short- and long-term leaching behaviour and characteristic properties of materials.
The document has been developed to measure the pH-dependent release of inorganic and organic substances from soil and soil-like material as well as to produce eluates for subsequent ecotoxicological testing. For ecotoxicological testing, see ISO 15799 and ISO 17616. The equilibrium condition, as defined in this document, is established by the addition of predetermined amounts of acid or base to reach desired final pH values.
NOTE 1 Volatile organic substances include the low molecular weight substances in mixtures such as mineral oil.
NOTE 2 It is not always possible to optimize test conditions simultaneously for inorganic and organic substances and optimum test conditions can also vary between different groups of organic substances. Test requirements for organic substances are generally more stringent than those for inorganic substances. The test conditions suitable for measuring the release of organic substances will generally also be applicable to inorganic substances.
NOTE 3 Within the category of organic substances, a significant difference in behaviour exists between the more polar, relatively water-soluble compounds and apolar, hydrophobic organic substances (HOCs). In the latter case, mechanisms of release (e.g. particle-bound or dissolved organic carbon-bound) can be more crucial as well as sorption losses of soluble HOCs on different materials with which they come in contact (e.g. bottles, filters). The test and the results should be used for leaching of organic substances only with thorough consideration of the specific properties of the substances in question and the associated potential problems.
NOTE 4 For ecotoxicological testing, eluates representing the release of both inorganic and organic substances are needed. In this document, ecotoxicological testing is meant to include genotoxicological testing.
The test method produces eluates, which can subsequently be characterized by physical, chemical and ecotoxicological methods in accordance with existing standard methods. The test is not suitable for substances that are volatile under ambient conditions.
For the purposes of ecotoxicological tests, the relevant pH range (see 8.2) will usually be pH 5 to pH 9.
This test is mainly aimed at being used for routine and control purposes, and it cannot be used alone to describe all leaching properties of a soil. Additional leaching tests are needed for that extended goal. This document does not address issues related to health and safety. It only determines the leaching properties outlined in Clause 5.
Bodenbeschaffenheit - Elutionsverfahren für die anschließende chemische und ökotoxikologische Untersuchung von Boden und von Bodenmaterialien - Teil 4: Einfluss des pH–Wertes unter vorheriger Säure/Base-Zugabe (ISO 21268-4:2019)
Dieses Dokument legt ein Prüfverfahren fest, um Angaben über das kurzfristige und langfristige Elutionsverhalten und zu den charakteristischen Eigenschaften von Materialien zu erhalten.
Dieses Dokument wurde erstellt, um die pH abhängige Freisetzung anorganischer und organischer Substanzen aus Boden und bodenähnlichem Material zu untersuchen und um Eluate für nachfolgende ökotoxikologische Untersuchungen herzustellen. Hinsichtlich der ökotoxikologischen Prüfung siehe ISO 15799 und ISO 17616. Der Gleichgewichtszustand, wie er in diesem Dokument definiert ist, wird durch Zugabe von vorher bestimmten Mengen an Säure oder Base hergestellt, um die gewünschten endgültigen pH Werte zu erreichen.
ANMERKUNG 1 Zu den flüchtigen organischen Substanzen gehören niedermolekulare Substanzen in Gemischen wie z. B. Mineralöl.
ANMERKUNG 2 Es ist nicht immer möglich, die Prüfbedingungen gleichzeitig für anorganische und organische Substanzen zu optimieren, und die optimalen Prüfbedingungen können sich auch für unterschiedliche Gruppen von organischen Substanzen unterscheiden. Die Prüfanforderungen für organische Substanzen sind im Allgemeinen strenger als für anorganische Substanzen. Die Prüfbedingungen, die für die Messung der Freisetzung von organischen Substanzen geeignet sind, sind im Allgemeinen auch auf anorganische Substanzen anwendbar.
ANMERKUNG 3 Innerhalb der Kategorie organischer Substanzen besteht ein deutlicher Verhaltensunterschied zwischen den eher polaren, relativ wasserlöslichen Verbindungen und den nichtpolaren, hydrophoben organischen Substanzen (en: hydrophobic organic substances, HOCs). Im letzteren Fall können die Freisetzungsmechanismen (z. B. teilchengebundene oder gelöste organische Kohlenstoffverbindungen) sowie die Sorptionsverluste löslicher HOCs bei unterschiedlichen Materialien, mit denen sie in Kontakt kommen (z. B. Flaschen, Filter), von entscheidenderer Bedeutung sein. Die Prüfung und die Ergebnisse sollten nur unter sorgfältiger Berücksichtigung der spezifischen Eigenschaften der zu betrachtenden Substanzen und damit verbundenen möglichen Problemen bei der Elution organischer Substanzen angewendet werden.
ANMERKUNG 4 Für ökotoxikologische Untersuchungen sind Eluate erforderlich, die die Freisetzung sowohl von anorganischen als auch von organischen Substanzen widerspiegeln. Im vorliegenden Dokument umfasst die ökotoxi-kologische Untersuchung auch die genotoxikologische Untersuchung.
Durch das Prüfverfahren werden Eluate hergestellt, die anschließend mit physikalischen, chemischen und ökotoxikologischen Verfahren nach bestehenden Standardverfahren charakterisiert werden können. Die Prüfung ist nicht geeignet für Substanzen, die unter Umgebungsbedingungen flüchtig sind.
Für die Durchführung ökotoxikologischer Untersuchungen liegt der betreffende pH Wert-Bereich (siehe 8.2) üblicherweise zwischen 5 und 9.
Dieses Prüfverfahren ist hauptsächlich darauf ausgerichtet, für Routine und Kontrollzwecke angewendet zu werden; es ist allein nicht ausreichend, um alle Elutionseigenschaften eines Bodens zu beschreiben. Für diese erweiterte Zielsetzung sind weitere Elutionstests erforderlich. Dieses Dokument befasst sich nicht mit gesundheitlichen und sicherheitstechnischen Belangen. Es dient nur der Bestimmung der in Abschnitt 5 dargestellten Elutionseigenschaften.
Qualité du sol - Modes opératoires de lixiviation en vue d'essais chimiques et écotoxicologiques ultérieurs des sols et matériaux du sol - Partie 4: Essai de dépendance au pH avec ajout initial d'acide/base (ISO 21268-4:2019)
Le présent document spécifie un essai permettant d'obtenir des informations sur le comportement à la lixiviation à court terme et à long terme ainsi que sur les propriétés caractéristiques des matériaux.
Le présent document a été conçu pour étudier le relargage, en fonction du pH, de substances organiques et inorganiques à partir du sol et des matériaux analogues au sol et produire des éluats destinés aux essais écotoxicologiques ultérieurs. Pour en savoir plus sur les essais écotoxicologiques, voir l'ISO 15799 et l'ISO 17616. L'état d'équilibre tel que défini dans le présent document s'obtient en ajoutant des quantités prédéterminées d'acide ou de base afin d'atteindre les valeurs de pH finales désirées.
NOTE 1 Les substances organiques volatiles incluent les substances de faible masse moléculaire contenues dans des mélanges tels que les huiles minérales.
NOTE 2 Il n'est pas toujours possible d'optimiser les conditions d'essai à la fois pour les substances organiques et les substances inorganiques, et les conditions d'essai optimales peuvent également varier entre différents groupes de substances organiques. Pour les substances organiques, les exigences des essais sont généralement plus contraignantes que pour les substances inorganiques. En général, les conditions d'essai adaptées pour mesurer le relargage des substances organiques seront également applicables aux substances inorganiques.
NOTE 3 Au sein de la catégorie des substances organiques, une différence de comportement notable existe entre les composés les plus polaires, relativement solubles dans l'eau et les substances organiques hydrophobes (COH), apolaires. Concernant ces derniers, les mécanismes de relargage (par exemple liés à des particules ou liés au carbone organique dissous) peuvent avoir plus d'importance, de même que les pertes dues à la sorption de COH solubles sur différents matériaux avec lesquels ils entrent en contact (par exemple flacons, filtres). Il convient d'utiliser les essais et les résultats pour la lixiviation des substances organiques, uniquement en ayant une connaissance approfondie des propriétés spécifiques des substances en question et des problèmes potentiels qui y sont associés.
NOTE 4 Pour les essais écotoxicologiques, des éluats représentant le relargage des substances à la fois organiques et inorganiques sont nécessaires. Dans le présent document, les essais écotoxicologiques englobent les essais génotoxicologiques.
Cette méthode d'essai produit des éluats qui peuvent ensuite être caractérisés par des méthodes physiques, chimiques et écotoxicologiques selon des méthodes normalisées existantes. L'essai n'est pas adapté aux substances qui sont volatiles dans des conditions ambiantes.
Pour les besoins des essais écotoxicologiques, la plage de pH applicable (voir 8.2) sera généralement comprise entre 5 et 9.
L'essai est principalement destiné aux fins de contrôle et d'analyse de routine, et il ne peut être utilisé seul pour décrire toutes les propriétés de lixiviation d'un sol. D'autres essais sont nécessaires pour atteindre cet objectif plus large. Le présent document ne traite pas des problèmes liés à la santé et à la sécurité. Il permet uniquement de déterminer les propriétés de lixiviation telles que décrites à l'Article 5.
Kakovost tal - Postopki izluževanja za nadaljnje kemijsko in ekotoksikološko preskušanje tal in tlem podobnih materialov - 4. del: Vpliv pH na izluževanje z začetnim dodatkom kisline ali baze (ISO 21268-4:2019)
Ta standard določa preskus za pridobitev informacij o kratkoročnem in dolgoročnem izluževanju ter značilnih lastnostih materialov. Dokument je bil pripravljen za merjenje od pH odvisnega sproščanja anorganskih in organskih snovi iz prsti in prsti podobnih materialov ter za izdelavo izlužkov za nadaljnje ekotoksikološke preskuse. Za ekotoksikološke preskuse glej ISO 15799 in ISO 17616. Ravnotežno stanje, kot je opredeljeno v tem dokumentu, je določeno z dodajanjem vnaprej določenih količin kisline ali baze, da se dosežejo želene končne vrednosti pH. Preskusna metoda proizvede izlužke, ki jih je nato mogoče določiti s fizikalnimi, kemijskimi in ekotoksikološkimi metodami v skladu z obstoječimi standardnimi metodami. Preskus ni primeren za snovi, ki so hlapne pri okoljskih pogojih. Za namen ekotoksikoloških preskusov bo ustrezni obseg vrednosti pH običajno od pH 5 do pH 9 (glej točko 8.2). Ta preskus se uporablja predvsem za rutinske in kontrolne namene, preskusa pa ni mogoče uporabiti samostojno za opis vseh izluževalnih lastnosti tal. Za ta razširjeni cilj so potrebni dodatni izluževalni preskusi. Ta dokument ne obravnava vprašanj v zvezi z zdravjem in varnostjo, ampak zgolj določa izluževalne lastnosti, opisane v točki 5.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-januar-2020
Nadomešča:
SIST-TS CEN ISO/TS 21268-4:2010
Kakovost tal - Postopki izluževanja za nadaljnje kemijsko in ekotoksikološko
preskušanje tal in tlem podobnih materialov - 4. del: Vpliv pH na izluževanje z
začetnim dodatkom kisline ali baze (ISO 21268-4:2019)
Soil quality - Leaching procedures for subsequent chemical and ecotoxicological testing
of soil and soil-like materials - Part 4: Influence of pH on leaching with initial acid/base
addition (ISO 21268-4:2019)
Bodenbeschaffenheit - Elutionsverfahren für die anschließende chemische und
ökotoxikologische Untersuchung von Boden und von Bodenmaterialien - Teil 4: Einfluss
des pH–Wertes unter vorheriger Säure/Base-Zugabe (ISO 21268-4:2019)
Qualité du sol - Modes opératoires de lixiviation en vue d'essais chimiques et
écotoxicologiques ultérieurs des sols et matériaux du sol - Partie 4: Essai de
dépendance au pH avec ajout initial d'acide/base (ISO 21268-4:2019)
Ta slovenski standard je istoveten z: EN ISO 21268-4:2019
ICS:
13.080.05 Preiskava tal na splošno Examination of soils in
general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN ISO 21268-4
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2019
EUROPÄISCHE NORM
ICS 13.080.05 Supersedes CEN ISO/TS 21268-4:2009
English Version
Soil quality - Leaching procedures for subsequent chemical
and ecotoxicological testing of soil and soil-like materials -
Part 4: Influence of pH on leaching with initial acid/base
addition (ISO 21268-4:2019)
Qualité du sol - Modes opératoires de lixiviation en vue Bodenbeschaffenheit - Elutionsverfahren für die
d'essais chimiques et écotoxicologiques ultérieurs des anschließende chemische und ökotoxikologische
sols et matériaux analogues au sol - Partie 4: Essai de Untersuchung von Boden und von Bodenmaterialien -
dépendance au pH avec ajout initial d'acide/de base Teil 4: Einfluss des pH-Wertes unter vorheriger
(ISO 21268-4:2019) Säure/Base-Zugabe (ISO 21268-4:2019)
This European Standard was approved by CEN on 6 October 2019.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 21268-4:2019 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
European foreword
This document (EN ISO 21268-4:2019) has been prepared by Technical Committee ISO/TC 190 "Soil
quality" in collaboration with Technical Committee CEN/TC 444 “Test methods for environmental
characterization of solid matrices” the secretariat of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by June 2020, and conflicting national standards shall be
withdrawn at the latest by June 2020.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes CEN ISO/TS 21268-4:2009.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 21268-4:2019 has been approved by CEN as EN ISO 21268-4:2019 without any
modification.
INTERNATIONAL ISO
STANDARD 21268-4
First edition
2019-10
Soil quality — Leaching procedures
for subsequent chemical and
ecotoxicological testing of soil and
soil-like materials —
Part 4:
Influence of pH on leaching with initial
acid/base addition
Qualité du sol — Modes opératoires de lixiviation en vue d'essais
chimiques et écotoxicologiques ultérieurs des sols et matériaux
analogues au sol —
Partie 4: Essai de dépendance au pH avec ajout initial d'acide/de base
Reference number
ISO 21268-4:2019(E)
©
ISO 2019
ISO 21268-4:2019(E)
© ISO 2019
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
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Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
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Published in Switzerland
ii © ISO 2019 – All rights reserved
ISO 21268-4:2019(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Principle . 3
5 Reagents . 4
6 Apparatus . 4
7 Sample pretreatment . 6
7.1 Preparation of laboratory sample and specification of particle size . 6
7.2 Preparation of test sample . 6
7.3 Determination of the dry matter content and of water content . 6
7.4 Preparation of the test portion . 7
8 Procedure. 7
8.1 Contact time . 7
8.2 pH-range . 7
8.3 Leaching test . 8
8.3.1 General. 8
8.3.2 Preparation of leachants . 8
8.3.3 Leaching step . 9
8.3.4 Liquid/solid separation step .10
8.4 Natural pH .11
8.5 Further preparation of the eluate for analysis.11
8.6 Blank test .11
9 Calculation .12
10 Test report .12
11 Analytical determination .13
11.1 General .13
11.2 Blank test information .13
12 Performance characteristics .13
Annex A (informative) Example of a specific liquid-solid separation procedure for soil samples .14
Annex B (informative) Operation and uses of the test — Influence of pH on the leaching
behaviour .16
Annex C (informative) Preliminary determination of the acid/base consumption .20
Annex D (informative) Repeatability and reproducibility data .24
Annex E (informative) Calculation of centrifugation duration depending on centrifugation
speed and rotor dimensions.28
Bibliography .30
ISO 21268-4:2019(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 190, Soil quality, Subcommittee SC 7,
Impact assessment.
This first edition of ISO 21268-4 cancels and replaces ISO/TS 21268-4:2007, which has been technically
revised. The main changes compared to the previous edition are as follows:
— the maximum grain size has been changed to <2 mm as usual for soil;
— references in Clause 2 and the Bibliography have been updated;
— Clause 12 “Performance characteristics” has been technically revised;
— a new informative Annex D “Repeatability and reproducibility data” has been added;
— a new informative Annex E "Calculation of centrifugation duration depending on centrifugation
speed and rotor dimensions" has been added.
A list of all parts in the ISO 21268 series can be found on the ISO website.
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 2019 – All rights reserved
ISO 21268-4:2019(E)
Introduction
In various countries, tests have been developed to characterize and assess the substances which can
be released from materials. The release of soluble substances upon contact with water is regarded as
a main mechanism of release, which results in a potential risk to the environment during the use or
disposal of materials. The intent of these tests is to identify the leaching properties of materials. The
[1]
complexity of the leaching process makes simplifications necessary .
Not all of the relevant aspects of leaching behaviour can be addressed in one standard.
Tests to characterize the behaviour of materials can generally be divided into three categories
addressed in ISO 18772 and EN 12920. The relationships between these tests are summarized below.
“Basic characterization” tests are used to obtain information on the short- and long-term leaching
behaviour and characteristic properties of materials. Liquid/solid ratios (L/S), leachant composition,
factors controlling leachability, such as pH, redox potential, complexing capacity, role of dissolved
organic carbon (DOC), ageing of material and physical parameters, are addressed in these defined tests.
“Compliance” tests are used to determine whether the material complies with a specific behaviour or
with specific reference values. These tests focus on key variables and leaching behaviour previously
identified by basic characterization tests.
“On-site verification” tests are used as a rapid check to confirm that the material is the same as that
which has been subjected to the compliance test(s). On-site verification tests are not necessarily
leaching tests.
The test procedure described in this method belongs to category a) “Basic characterization” tests.
This document was originally elaborated on the basis of CEN/TS 14429:2005. Especially, modifications
considering requirements on subsequent ecotoxicological testing and analysis of organic substances
[5]
have been included. Validation results have been adopted from US-EPA .
INTERNATIONAL STANDARD ISO 21268-4:2019(E)
Soil quality — Leaching procedures for subsequent
chemical and ecotoxicological testing of soil and soil-like
materials —
Part 4:
Influence of pH on leaching with initial acid/base addition
1 Scope
This document specifies a test to obtain information on the short- and long-term leaching behaviour
and characteristic properties of materials.
The document has been developed to measure the pH-dependent release of inorganic and organic
substances from soil and soil-like material as well as to produce eluates for subsequent ecotoxicological
testing. For ecotoxicological testing, see ISO 15799 and ISO 17616. The equilibrium condition, as defined
in this document, is established by the addition of predetermined amounts of acid or base to reach
desired final pH values.
NOTE 1 Volatile organic substances include the low molecular weight substances in mixtures such as mineral oil.
NOTE 2 It is not always possible to optimize test conditions simultaneously for inorganic and organic
substances and optimum test conditions can also vary between different groups of organic substances. Test
requirements for organic substances are generally more stringent than those for inorganic substances. The test
conditions suitable for measuring the release of organic substances will generally also be applicable to inorganic
substances.
NOTE 3 Within the category of organic substances, a significant difference in behaviour exists between the
more polar, relatively water-soluble compounds and apolar, hydrophobic organic substances (HOCs). In the latter
case, mechanisms of release (e.g. particle-bound or dissolved organic carbon-bound) can be more crucial as well
as sorption losses of soluble HOCs on different materials with which they come in contact (e.g. bottles, filters).
The test and the results should be used for leaching of organic substances only with thorough consideration of
the specific properties of the substances in question and the associated potential problems.
NOTE 4 For ecotoxicological testing, eluates representing the release of both inorganic and organic substances
are needed. In this document, ecotoxicological testing is meant to include genotoxicological testing.
The test method produces eluates, which can subsequently be characterized by physical, chemical and
ecotoxicological methods in accordance with existing standard methods. The test is not suitable for
substances that are volatile under ambient conditions.
For the purposes of ecotoxicological tests, the relevant pH range (see 8.2) will usually be pH 5 to pH 9.
This test is mainly aimed at being used for routine and control purposes, and it cannot be used alone
to describe all leaching properties of a soil. Additional leaching tests are needed for that extended goal.
This document does not address issues related to health and safety. It only determines the leaching
properties outlined in Clause 5.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 21268-4:2019(E)
ISO 5667-3, Water quality — Sampling — Part 3: Preservation and handling of water samples
ISO 7027-1, Water quality — Determination of turbidity— Part 1: Quantitative methods
ISO 10523, Water quality — Determination of pH
ISO 11465, Soil quality — Determination of dry matter and water content on a mass basis —
Gravimetric method
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
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/
3.1
leaching test
test during which a material is put into contact with a leachant (3.2) under strictly defined conditions
and some substances of the material are extracted
3.2
leachant
liquid used in a leaching test (3.1)
Note 1 to entry: For the purpose of this document, the leachant is specified in 6.1
3.3
eluate
solution recovered from a leaching test (3.1)
Note 1 to entry: Eluate is also referred to as leachate.
3.4
liquid to solid ratio
L/S
ratio between the total volume of liquid (L in litres), which in this extraction is in contact with the soil
sample, and the dry mass of the sample (S in kg of dry matter)
Note 1 to entry: L/S is expressed in litres per kilogram (l/kg).
3.5
dry matter content
w
dm
ratio, expressed in percent, between the mass of the dry residue, determined in accordance with
ISO 11465, and the corresponding raw mass
3.6
water content
w
HO
ratio, expressed in percent, between the mass of water contained in the material as received and the
corresponding dry residue of the material
Note 1 to entry: The basis for the calculation of the water content is the mass of the dry residue in this document,
as specified in ISO 11465 (for the determination of the water content of soil).
2 © ISO 2019 – All rights reserved
ISO 21268-4:2019(E)
3.7
laboratory sample
sample or subsample(s) sent to or received by the laboratory
3.8
test sample
sample, prepared from the laboratory sample (3.7), from which test portions (3.9) are removed for
testing or analysis
3.9
test portion
quantity of material of appropriate size for measurement of the concentration or other properties of
interest taken from the test sample (3.8)
Note 1 to entry: The test portion can be taken from the laboratory sample (3.7) directly if no pre-treatment of the
sample is required, but usually it is taken from the test sample.
Note 2 to entry: A unit or increment of proper homogeneity, size and fineness, needing no further preparation,
can be a test portion.
3.10
soil-like material
excavated soil, dredged materials, manufactured soils, treated soils and fill materials
4 Principle
The test portions, which originally or after suitable pre-treatment have a particle size less than or equal
to 2 mm, are brought into contact with water containing a low concentration (0,001 mol/l) of calcium
chloride or demineralised water (5.1) under defined conditions. Several separate test portions (up to
eight) are leached at a fixed L/S ratio (L/S = 10 l/kg) with leachants containing different preselected
amounts of acid or base in order to reach stationary pH values at the end of the extraction period (see
8.4). Each leachant is added in three steps in the beginning of the test. In the full test, eight final pH-
values are required, covering the range pH 4 to pH 12 (both included, i.e. the lowest value 4 and the
highest value 12). The amount of acid or base needed to cover the pH range can be derived from the
results of a preliminary titration, from available experimental data on the material to be tested or
from an arbitrary division of the predetermined maximum consumption of acid and base. The tests are
carried out at a fixed contact time at the end of which an equilibrium condition can be assumed to be
reached for most substances in most soil-like materials to be characterized. The equilibrium condition,
as defined in this document, is verified at the end of the extraction period.
The results are expressed in milligrams per litre (mg/l) of substances for each final pH value. For each
+
final pH value, the quantity of acid that is added is also expressed in mol H /kg dry matter and the
+
quantity of base that is added is expressed as negative mol H /kg dry matter.
NOTE 1 This test may also be performed using continuous pH control. The results are generally consistent
(see Annex B).
NOTE 2 Other expressions of results are possible (including mg/kg of dry matter).
From the amount of acid and base used to reach a given end pH, the acid neutralization capacity (ANC)
or base neutralization capacity (BNC) of the soil or soil-like material can also be determined.
NOTE 3 The pH range covered by the test can be restricted to a pH range relevant for the specific material and
the considered problem (see 8.2).
NOTE 4 The leachant is made with 0,001 mol/l CaCl to minimize the mobilization of DOC caused by a too-
low ionic strength of the leachant. At the level of 0,001 mol/l CaCl the complexation of metals with chloride is
considered to be negligible.
ISO 21268-4:2019(E)
The substances in the eluate(s) are measured using methods developed for water analysis adapted
to meet criteria for analysis of eluates. The eluate may also be applied for subsequent ecotoxicity or
genotoxicity testing.
After the test, the leaching conditions (in terms of pH, electrical conductivity, DOC and, optionally,
turbidity and redox potential dictated by the material) are recorded.
NOTE 5 These parameters often control the leaching behaviour of soil-like materials and are therefore
important for checking the leaching test.
5 Reagents
Reagents used shall be of analytical grade purity.
5.1 Demineralized water or deionized water or water of equivalent purity (5 < pH < 7,5) with
a conductivity of < 0,5 mS/m in accordance with grade 3 specified in ISO 3696 made to 0,001 mol/l CaCl .
5.2 Calcium chloride (CaCl · 2 H O), analytical grade.
2 2
5.3 Sodium azide (NaN ), analytical grade.
5.4 Nitric acid (pro-analysis) (HNO ), 0,1 mol/l to 5 mol/l, and 0,1 mol/l rinsing solution.
5.5 Sodium hydroxide (NaOH) or potassium hydroxide (KOH), 0,1 mol/l to 5 mol/l.
+ +
NOTE The use of KOH instead of NaOH may enhance the leaching of certain cations such as NH and Cs by
cation exchange.
5.6 Organic solvent (acetone, analytical grade) for rinsing and cleaning.
6 Apparatus
6.1 Borosilicate glass, of high purity in accordance with ISO 5667-3, with a nominal volume of 1 l,
glass bottles having caps of inert material, for example PTFE (polytetrafluoroethylene). Rinsing is
compulsory, and it should be assured that previously used bottles have no background level of analyte.
NOTE 1 If only inorganic parameters are analysed, alternative materials such as HDPE/PP bottles are
appropriate, except for unpreserved samples for mercury analysis.
NOTE 2 To prevent organic compounds from degradation by light use a dark room, dark colored glassware or
place a layer of aluminium-foil around the leaching equipment.
If Boron analyses are necessary, any plastics bottles can be used, e.g. PTFE (polytetrafluoroethylene).
The volume of 1 l is selected in combination with the mass, m , of 60 g, in order to minimize headspace
D
in the bottle. For m = 15 g and 30 g, bottle sizes of, respectively, 250 ml and 500 ml shall be used. In
D
the case of materials with low density, deviation from this requirement can be necessary while still
ensuring minimize headspace. This deviation should be reported.
NOTE 3 Glass of high quality is considered adequate for both metals and organic substances, particularly since
the pH range usually covered in soil testing does not reach the conditions (pH > 12 and pH < 3) where the glass
itself may be partially dissolved. For ecotoxicity testing, eluates with both inorganic and organic substances are
needed, which emphasizes the need to generate integrated eluates.
NOTE 4 Heat treatment of used glassware at 550 °C can be used to remove traces of analytes. However, this
treatment has been shown to increase adsorption of organic substances from the air.
4 © ISO 2019 – All rights reserved
ISO 21268-4:2019(E)
−1 −1 −1
6.2 End-over-end tumbler (5 min to 10 min ) or roller table, rotating at about 10 min . Other
shaking devices may be used, provided that they can be shown to provide equivalent results. These
agitation devices are specified because excessive abrasion leading to significant particle size reduction
should be avoided.
6.3 Filtration apparatus, either a vacuum filtration device (between 2,5 kPa and 4,0 kPa) or
a high-pressure filtration apparatus (< 0,5 MPa). Rinsing is compulsory. When semi-volatile substances
are to be analysed, vacuum filtration shall not be used.
6.4 0,45 µm membrane filters, prerinsed or similarly cleaned (e.g. rinsed with 0,1 mol/l HNO (5.4)
and water (5.1) (only for analysis of inorganic substances).
The filters shall be chosen so as not to adsorb (or release) substances of interest.
NOTE This can be tested in preliminary experiments.
6.5 Glass fibre filters, with a degree of separation of 0,7 µm.
The filters shall be chosen so as not to adsorb (or release) substances of interest.
NOTE This can be tested in preliminary experiments.
6.6 Sieving equipment, with sieves of 2 mm nominal screen size.
NOTE Due to sieving, contamination of the sample can occur to an extent which affects the leaching of some
substances of concern, e.g. chromium, nickel and molybdenum from stainless steel equipment or plasticisers
from plastic sieves.
6.7 Centrifuge, operating at 20 000 g to 30 000 g using centrifuge tubes of FEP (fluorinated ethylene
propylene) or tubes of an alternative material, which is inert with regard to both inorganic and organic
compounds and suitable for high-speed centrifugation.
NOTE Potential sorption of hydrophobic organic substances to the centrifuge tubes can be tested in
preliminary experiments.
Alternatively, if a high-speed centrifuge is not available, a centrifuge operating at 2 000 g to 2 500 g
using glass bottles may be used in combination with increased centrifugation time. Cooling shall be
applied to maintain the desired temperature.
6.8 Glass bottles, with screw cap and PTFE (polytetrafluoroethylene) inlay for centrifugation.
6.9 Device for measuring electrical conductivity.
6.10 pH meter, in accordance with ISO 10523.
6.11 Redox potential meter (optional).
6.12 Balance, with an accuracy of at least 0,1 g.
6.13 Sample splitter, for sub-sampling of laboratory samples (optional).
6.14 Turbidity meter, as specified in ISO 7027-1.
6.15 Crushing equipment, a jaw crusher.
NOTE Due to particle size reduction, contamination of the sample can occur to an extent which affects the
leaching of some substances of concern, e.g. chromium, nickel and molybdenum from stainless steel equipment.
ISO 21268-4:2019(E)
7 Sample pretreatment
7.1 Preparation of laboratory sample and specification of particle size
A representative laboratory sample of at least 2 kg (dry matter) is obtained (e.g. as described in
ISO 18400 series and ISO 23909) and shall be stored in closed packages and at low temperatures (4 °C),
in order to avoid unwanted changes in the material (see e.g. ISO 18400-105).
The test shall be carried out on soil or soil-like material sieved to < 2 mm (e.g. as described in
ISO 11464). Oversized material of natural origin in the sample shall be separated and discarded. The
type and amount of all discarded material shall be reported. If oversized material of anthropogenic
origin is present and assumed to contain substances of interest, this part can be subject to alternative
sample preparation or testing.
If the laboratory sample cannot be homogenised or sieved because of its water content, it is allowed in
this case only to dry the laboratory sample (e.g. as described in ISO 11464). The drying temperature
shall not exceed 30 °C.
NOTE 1 Sieving and drying at more than 30 °C, as well as crushing, can lead to a loss of semi-volatile substances
(inorganic and organic) and can alter the leaching characteristics).
NOTE 2 Due to sieving, contamination of the sample can occur to an extent that affects the leaching of some
substances of concern, e.g. chromium, nickel and molybdenum from stainless steel equipment or plasticisers
from plastic sieves.
7.2 Preparation of test sample
Use a sample splitter (6.13) or apply coning and quartering to split the laboratory sample and obtain a test
sample. The size of test sample required depends on the volume of eluate needed for the specific purpose
and the subsequent chemical analysis and/or ecotoxicological tests to be carried out on the eluate.
NOTE 1 If needed for chemical analysis or ecotoxicological testing, larger volumes of eluate can be obtained
by combining eluates from replicate tests after centrifugation (or filtration). Alternatively, larger volumes of
eluate may also be produced in a single test, provided that the ratios in terms of L/S and minimum headspace are
maintained.
NOTE 2 The required amount of the test sample is dependent on the particle size distribution of the soil to be
analysed (see ISO 23909). The specified sample amount will generally be adequate. In specific cases, a smaller
sample amount can be accepted, for instance, if for specific reasons less material is available, provided that the
test can be carried out as specified in 7.2 to 7.4.
7.3 Determination of the dry matter content and of water content
The whole test sample, complying with the size criterion in 7.2, shall not be further dried. The moisture
content of the test sample shall be determined on a separate test portion at (105 ± 5) °C. If the soil sample
is air-dried prior to testing, the dry matter content w of the air-dried sample shall be determined
dm
as well. This shall be taken into account when adjusting the L/S. The dry mass of the sample shall be
determined at (105 ± 5) °C, in accordance with ISO 11465, and the dry matter content calculated with
Formula (1):
wm=×100 /m (1)
dm DW
where
w is the dry matter content, expressed in percent (%);
dm
m is the mass of the dried sample, expressed in kilograms (kg);
D
m is the mass of undried sample, expressed in kilograms (kg).
W
6 © ISO 2019 – All rights reserved
ISO 21268-4:2019(E)
The water content ( w in percent) is calculated with Formula (2):
HO
wm=×100 −mm/ (2)
()
HO WD D
NOTE If volatile or unstable compounds are present in the soil sample, this gravimetric method cannot be
used for accurate determination of the water content.
7.4 Preparation of the test portion
Prepare from the test sample at least eight test portions. Based on sample heterogeneity and eluate
volume requirement for analysis, the test portion size shall be either m = (15 ± 1) g, (30 ± 1) g or
D
(60 ± 1) g [measured with an accuracy of 0,1 g (6.12)] of dry mass (m ) following Formula (3).
D
mm=×100 /w (3)
Ddm
Use a sample splitter (6.13) or apply coning and quartering to split the sample.
NOTE Sample splitting or coning-and-quartering can lead to loss of semi-volatile substances (inorganic and
organic).
In view of the minimum requirements of eluate volume for analytical purposes, it may be necessary
to use a larger test portion and a correspondingly larger volume of leachant. This deviation from this
document shall be specified in the test report.
If the test is performed on an air-dried sample, use w instead of w to determine the sample mass
dm,AD dm
of the test portion.
8 Procedure
8.1 Contact time
The leaching procedure consists of three defined stages:
— Period A (acid/base addition) from t to (t + 4 h) for acid/base additions in three steps;
0 0
— Period B (equilibration period) from (t + 4 h) to (t + 44 h) equilibration period;
0 0
— Period C (verification period) from (t + 44 h) to (t + 48 h) for verification of equilibrium condition.
0 0
The total contact period (A + B + C) is 48 h.
8.2 pH-range
The full test shall cover the range pH 4 to pH 12 (both included, i.e. the lowest value ≥ 4 and the highest
value ≤ 12) with eight pH values tested, including the natural pH (without acid or base addition). The
maximum difference between two consecutive pH values shall not exceed 1,5 pH units.
To ensure that the appropriate pH values can be obtained in one run, additional bottles can be prepared
of which only the ones with the desired final pH values are retained for analysis.
The pH range covered by the test may be restricted to a pH range relevant to the specific material and
the considered problem. The pH range to be covered may depend on the specific properties of the soil
material, the available information on this material and the questions to be answered by performing
the test. The number of pH levels considered can be reduced, correspondingly, for example, for the
purpose of ecotoxicological tests. The relevant pH range will usually be pH 5 to pH 9.
ISO 21268-4:2019(E)
8.3 Leaching test
8.3.1 General
The following procedure applies to each of the chosen pH values to be tested.
8.3.2 Preparation of leachants
+
Identify the acid or base consumption for reaching the relevant pH values as A (mol H /kg dry matter)
–
or B (mol OH /kg dry matter) and the total volume of leachant.
NOTE The acid or base consumption for the considered pH values can be derived from available information,
from the preliminary procedures in Annex B, or from information in Annex C.
Calculate the volume V of liquid to establish an L/S ratio of 10 ± 0,2 (l/kg) for the actual size of test
L
portion m (see 7.4), including the volume of acid or base, in accordance with Formula (4):
Vw=−10 / ρ ×100 ×m (4)
)
LH O ( D
HO
2
where
V is the volume of leachant used (l);
L
m is the dry mass of the test portion (kg);
D
is the density of water (usually taken as 1 kg/l);
ρ
HO
is the water content for the test portion (%).
w
HO
Prepare the leachant from 0,001 mol/l CaCl (see 5.1) and acid or base (see 5.4 or 5.5) according to the
acid/base consumption for the relevant pH.
Prepare the acid-adjusted leachant in accordance with Formula (5) and Formula (6):
VV=+V (5)
Ld A
nm×
AD
V = (6)
A
C
A
where
V is the volume of prepared leachant, in millilitres (ml);
L
V is the volume of 0,001 mol/l CaCl used, in millilitres (ml);
d 2
V is the volume of acid needed, in millilitres (ml);
A
+
n is the acid consumption for the particular pH, in mol H /kg dry matter;
A
m is the dry mass of the test portion, in grams (g) (see 7.4);
D
C is the concentration of the acid, in moles per litre (mol/l) (see 5.4).
A
Prepare the base-adjusted leachant in accordance with Formula (7) and Formula (8):
VV=+V (7)
Ld B
8 © ISO 2019 – All rights reserved
ISO 21268-4:2019(E)
nm×
BD
V = (8)
B
C
B
where
V is the volume of prepared leachant, in millilitres (ml);
L
V is the volume of 0,001 mol/l CaCl used, in millilitres (ml);
d 2
V is the volume of base needed, in millilitres (ml);
B
–
n is the base consumption for the particular pH, in mol OH /kg dry matter;
B
m is the dry mass of the test portion, in grams (g) (see 7.4);
D
C is the concentration of the base, in moles per litre (mol/l) (see 5.5).
B
Split the volume V of leachant into three equal parts, V /3.
L L
8.3.3 Leaching step
Carry out the test at a temperature of (22 ± 3) °C.
Select the appropriate bottle size according to the test portion size. For m = 15 g, 30 g and 60 g, this
D
means bottle sizes of, respectively, 250 ml, 500 ml and 1 000 ml.
Place one of the test portions in the rinsed bottle (see 6.1).
Add the leachant volume, V /3, at three different times:
L
— first fraction at t ;
— second fraction at t + 30 min;
— third fraction at t + 2 h.
Close the bottle and agitate the suspension (see 6.2) between each leachant addition. Measure and
record the pH (see below for instructions), and, if deviations are observed from the expected pH at that
time, prepare additional bottles with modified acid/base additions.
Development of carbon dioxide should be taken into account when using acidic leachants. This may lead
to pressure build-up. When this is expected or observed, the pressure can be relieved by opening the
bottle a few times during the test. Main gas production will, however, take place in the first period of
acid addition.
Continue to agitate after the last leachant addition until t = t + 48 h.
Measuring and recording of the pH:
— Measure and record the pH at t + 4 h, t + 44 h, t + 48 h.
0 0 0
— Since the pH is measured directly in the suspension, rinse the pH electrode thoroughly and dry
softly before and between uses in order not to contaminate the suspension.
— For the measurement of the pH, stop the agitation and allow the mix to settle for 5 min. Measure the
pH by i
...
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