Soil quality - Parameters for geochemical modelling of leaching and speciation of constituents in soils and materials - Part 4: Extraction of humic substances from solid samples (ISO 12782-4:2012)

This part of ISO 12782 specifies a procedure to determine the concentration of humic substances in soil or materials. Materials also include waste as given in the Introduction.

Bodenbeschaffenheit - Parameter zur geochemischen Modellierung der Elution und Speziation von Bestandteilen in Böden und Materialien - Teil 4: Extraktion von Huminstoffen aus Feststoffproben (ISO 12782-4:2012)

Der vorliegende Teil der ISO 12782 legt ein Verfahren zur Bestimmung der Konzentration von Huminstoffen in
Böden und in Materialien fest. Wie bereits in der Einleitung erwähnt, schließen Materialien ebenfalls Abfall ein.
ANMERKUNG Der Gehalt an Huminstoffen kann als Vorgabe in geochemischen Modellen verwendet werden.

Qualité du sol - Paramètres pour la modélisation géochimique de la lixiviation et de la spéciation des constituants des sols et des matériaux - Partie 4: Extraction des substances humiques des échantillons solides (ISO 12782-4:2012)

L'ISO 12782-4:2012 spécifie un mode opératoire permettant de déterminer la concentration des substances humiques dans le sol ou autres matériaux. Les autres matériaux incluent également les déchets. La teneur en substances humiques peut être utilisée comme une donnée d'entrée dans les modèles géochimiques.

Kakovost tal - Parametri geokemijskega modeliranja izpiranja in speciacija sestavin v tleh in talnih materialih - 4. del: Ekstrakcija huminskih snovi iz trdnih vzorcev (ISO 12782-4:2012)

Ta del standarda ISO 12782 opisuje postopek za določevanje koncentracije huminskih snovi v tleh ali talnih materialih. Med materiale spadajo tudi odpadki, opisani v uvodu.

General Information

Status
Published
Public Enquiry End Date
30-Apr-2011
Publication Date
21-Apr-2013
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
04-Apr-2013
Due Date
09-Jun-2013
Completion Date
22-Apr-2013

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 12782-4:2013
01-maj-2013
Kakovost tal - Parametri geokemijskega modeliranja izpiranja in speciacija
sestavin v tleh in talnih materialih - 4. del: Ekstrakcija huminskih snovi iz trdnih
vzorcev (ISO 12782-4:2012)
Soil quality - Parameters for geochemical modelling of leaching and speciation of
constituents in soils and materials - Part 4: Extraction of humic substances from solid
samples (ISO 12782-4:2012)
Bodenbeschaffenheit - Parameter zur geochemischen Modellierung der Elution und
Speziation von Bestandteilen in Böden und Materialien - Teil 4: Extraktion von
Huminstoffen aus Feststoffproben (ISO 12782-4:2012)
Qualité du sol - Paramètres pour la modélisation géochimique de la lixiviation et de la
spéciation des constituants des sols et des matériaux - Partie 4: Extraction des
substances humiques des échantillons solides (ISO 12782-4:2012)
Ta slovenski standard je istoveten z: EN ISO 12782-4:2012
ICS:
13.080.10 .HPLMVNH]QDþLOQRVWLWDO Chemical characteristics of
soils
SIST EN ISO 12782-4:2013 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 12782-4:2013

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SIST EN ISO 12782-4:2013


EUROPEAN STANDARD
EN ISO 12782-4

NORME EUROPÉENNE

EUROPÄISCHE NORM
June 2012
ICS 13.080.05
English Version
Soil quality - Parameters for geochemical modelling of leaching
and speciation of constituents in soils and materials - Part 4:
Extraction of humic substances from solid samples (ISO 12782-
4:2012)
Qualité du sol - Paramètres pour la modélisation
Bodenbeschaffenheit - Parameter zur geochemischen
géochimique de la lixiviation et de la spéciation des Modellierung der Elution und Speziation von Bestandteilen
constituants des sols et des matériaux - Partie 4: Extraction in Böden und Materialien - Teil 4: Extraktion von
des substances humiques des échantillons solides (ISO Humusstoffen aus Feststoffproben (ISO 12782-4:2012)
12782-4:2012)
This European Standard was approved by CEN on 31 May 2012.

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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12782-4:2012: E
worldwide for CEN national Members.

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SIST EN ISO 12782-4:2013
EN ISO 12782-4:2012 (E)
Contents Page
Foreword .3

2

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SIST EN ISO 12782-4:2013
EN ISO 12782-4:2012 (E)
Foreword
This document (EN ISO 12782-4:2012) has been prepared by Technical Committee ISO/TC 190 "Soil quality"
in collaboration with Technical Committee CEN/TC 345 “Characterization of soils” 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 December 2012, and conflicting national standards shall be withdrawn
at the latest by December 2012.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN/CENELEC Internal Regulations, the national standards organisations 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, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 12782-4:2012 has been approved by CEN as a EN ISO 12782-4:2012 without any
modification.

3

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SIST EN ISO 12782-4:2013

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SIST EN ISO 12782-4:2013
INTERNATIONAL ISO
STANDARD 12782-4
First edition
2012-06-01
Soil quality — Parameters for geochemical
modelling of leaching and speciation of
constituents in soils and materials —
Part 4:
Extraction of humic substances from
solid samples
Qualité du sol — Paramètres pour la modélisation géochimique de la
lixiviation et de la spéciation des constituants des sols et des matériaux —
Partie 4: Extraction des substances humiques des échantillons solides
Reference number
ISO 12782-4:2012(E)
©
ISO 2012

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SIST EN ISO 12782-4:2013
ISO 12782-4:2012(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved

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SIST EN ISO 12782-4:2013
ISO 12782-4:2012(E)
Contents Page
Foreword .iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Principle . 3
5 Apparatus . 3
6 Reagents . 4
7 Sample pretreatment . 5
7.1 Sample size . 5
7.2 Particle size reduction . 5
7.3 Determination of dry residue . 6
7.4 Test portion . 6
8 Procedure . 6
8.1 Preparation of DAX-8 resin . 6
8.2 Determination of total humic acid (HA), fulvic acid (FA) and hydrophilic organic carbon (Hy)
content in solid source materials . 7
9 Eluate treatment and storage . 7
10 Analytical determination . 7
11 Blank test . 7
12 Calculation . 8
12.1 General correction factors for the calculation of humic acid (HA), fulvic acid (FA),
hydrophilic organic carbon (Hy) and hydrophobic neutral organic carbon (HON) in liquid and
solid samples . 8
12.2 Concentration of total humic acid (HA), fulvic acid (FA), hydrophilic organic carbon (Hy) and
hydrophobic neutral organic carbon (HON) concentrations in solid samples . 9
13 Expression of results . 11
14 Test report . 11
15 Performance characteristics . 11
Annex A (informative) Schematic representation of the fractionation procedure .12
Annex B (informative) Validation of procedure .14
Annex C (informative) Conditions regarding centrifugation .19
Bibliography .22
© ISO 2012 – All rights reserved iii

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SIST EN ISO 12782-4:2013
ISO 12782-4:2012(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 12782-4 was prepared by Technical Committee ISO/TC 190, Soil quality, Subcommittee SC 7, Soil and
site assessment.
ISO 12782 consists of the following parts, under the general title Soil quality — Parameters for geochemical
modelling of leaching and speciation of constituents in soils and materials:
— Part 1: Extraction of amorphous iron oxides and hydroxides with ascorbic acid
— Part 2: Extraction of crystalline iron oxides and hydroxides with dithionite
— Part 3: Extraction of aluminium oxides and hydroxides with ammonium oxalate/oxalic acid
— Part 4: Extraction of humic substances from solid samples
— Part 5: Extraction of humic substances from aqueous samples
iv © ISO 2012 – All rights reserved

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SIST EN ISO 12782-4:2013
ISO 12782-4:2012(E)
Introduction
In addition to leaching procedures for subsequent chemical and ecotoxicological testing of soil and other
materials including waste, predictive models are becoming indispensable tools in the environmental risk
assessment of these materials. Models are particularly required when the results of laboratory leaching tests
are to be translated to specific scenarios in the field, with regard to assessing the risks of both contaminant
migration and bioavailability.
In the past few years, geochemical models have been shown to be valuable tools to be combined with the
data obtained from characterization leaching standards, such as pH-dependence and percolation tests. These
models have the advantage of being based on fundamental thermodynamic parameters that have a general
validity. In order to enable extrapolation of laboratory leaching data to the mobility and/or bioavailability of
a constituent in a specific field scenario, these models require additional input parameters for specific soil
properties (see Figure 1).
Key
1 experiment
2 geochemical speciation modelling
3 available metal concentration
4 dissolved humic substances
5 reactive (solid) surfaces
6 database with stability constants
7 computer program
8 assumptions
Figure 1 — Relationships between experimental data, as obtained from laboratory
leaching/extraction tests, and geochemical modelling of the speciation of a heavy metal
in the environment (modified after M. Gfeller & R. Schulin, ETH, Zürich)
Characterization leaching standards provide information on the concentrations of the contaminant of interest as
a function of, in particular, pH and liquid/solid (L/S) ratio. In addition, a more complete analysis of the leachates
also provides information on the major ion composition and dissolved organic carbon (DOC), parameters that
are particularly important for the chemical speciation of constituents through processes such as precipitation,
complexation and competition for adsorption on reactive mineral and organic surfaces in the soil. As illustrated
© ISO 2012 – All rights reserved v

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SIST EN ISO 12782-4:2013
ISO 12782-4:2012(E)
in Figure 1 for the example of copper, geochemical modelling enables calculation of the metal distribution
among these different chemical species in the system of interest. This provides necessary information for risk-
assessment purposes, as these different chemical forms play distinct roles in the mobility and bioavailability
of the metal in the soil. In addition to information obtained from the leaching standards (in their current state of
development/definition), two additional types of information are required.
a) The “available” (sometimes also referred to as “active” or “exchangeable”) concentration of the constituent
in the solid phase, as opposed to the total concentration determined by acid destruction of the solid matrix.
This “available” concentration can be obtained by leaching at low pH, a condition that can be obtained by
extending the pH range in the pH-dependent leaching test (ISO/TS 21268-4) down to pH ≈ 0,5 to pH ≈ 1.
b) The concentration of reactive organic and mineral surfaces in the soil, which constitute the major binding
(adsorption) sites for most constituents in the soil matrix.
The major reactive surfaces that control the binding of constituents by sorption processes to the soil matrix
are particulate organic matter and iron and aluminium (hydr)oxides. It is generally accepted that the reactivity
of these mineral and organic surfaces can strongly vary as a function of their specific surface area/crystallinity
[iron and aluminium (hydr)oxides] and composition (organic matter). When the results are intended to be used
for the above-described purposes of geochemical modelling in conjunction with leaching tests, it is important
that the methods be selective for reactive surfaces for which generic thermodynamic adsorption parameters
are also available for the most important major and trace elements.
These reactive surfaces have been identified in soils, as well as in a variety of other materials for which the
leaching of constituents is of relevance. It has been shown that the binding properties of these surfaces play
a generic role in the speciation and leaching of constituents among these different materials. As an example,
a similar geochemical modelling approach, using model input from the partial or complete ISO 12782 series,
[3] [4][5] [6]
has been successfully applied to different soils , amended soils , municipal incinerator bottom ash , steel
[7][8] [9] [10]
slag , bauxite residues , and recycled concrete aggregate . Hence, the scope of the ISO 12782 series
extends from soils to materials including soil amendments and waste materials.
This part of ISO 12782 aims to determine important reactive organic surfaces in soil and materials, for which
generic thermodynamic adsorption parameters exist, i.e. humic and fulvic acids. The procedure is based on
Reference [11], while generic thermodynamic adsorption parameters for humic and fulvic acids are available in
References [12] and [13].
Thermodynamic parameters for adsorption models other than those used in References [12] and [13] are also
available in the literature and may also be used to model the binding of constituents to humic and fulvic acids.
[14] [11]
The method is based on a conventional isolation and purification method that is also used by the
International Humic Substances Society (IHSS).
vi © ISO 2012 – All rights reserved

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SIST EN ISO 12782-4:2013
INTERNATIONAL STANDARD ISO 12782-4:2012(E)
Soil quality — Parameters for geochemical modelling of
leaching and speciation of constituents in soils and materials —
Part 4:
Extraction of humic substances from solid samples
1 Scope
This part of ISO 12782 specifies a procedure to determine the concentration of humic substances in soil or
other materials. Other materials also include waste. The content of humic substances can be used as input in
geochemical models.
2 Normative references
The following referenced documents are indispensable for the application 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 5667-3, Water quality — Sampling — Part 3: Preservation and handling of water samples
ISO 8245, Water quality — Guidelines for the determination of total organic carbon (TOC) and dissolved
organic carbon (DOC)
ISO 10381-1, Soil quality — Sampling — Part 1: Guidance on the design of sampling programmes
ISO 10381-2, Soil quality — Sampling — Part 2: Guidance on sampling techniques
ISO 10381-3, Soil quality — Sampling — Part 3: Guidance on safety
ISO 10381-4, Soil quality — Sampling — Part 4: Guidance on the procedure for investigation of natural, near-
natural and cultivated sites
ISO 10381-5, Soil quality — Sampling — Part 5: Guidance on the procedure for the investigation of urban and
industrial sites with regard to soil contamination
ISO 10381-6, Soil quality — Sampling — Part 6: Guidance on the collection, handling and storage of soil under
aerobic conditions for the assessment of microbiological processes, biomass and diversity in the laboratory
ISO 11464, Soil quality — Pretreatment of samples for physico-chemical analysis
ISO 11465, Soil quality — Determination of dry matter and water content on a mass basis — Gravimetric method
EN 14899, Characterization of waste — Sampling of waste materials — Framework for the preparation and
application of a sampling plan
EN 15002, Characterization of waste — Preparation of test portions from the laboratory sample
CEN/TR 15310-3, Characterization of waste — Sampling of waste materials — Part 3: Guidance on procedures
for sub-sampling in the field
© ISO 2012 – All rights reserved 1

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SIST EN ISO 12782-4:2013
ISO 12782-4:2012(E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
dissolved organic carbon
DOC
sum of organically bound carbon present in water originating from compounds (including cyanate and
thiocyanate) which will pass a membrane filter of pore size 0,45 µm
3.2
humic substance
HS
(partial) decomposition product from plant and animal tissue
NOTE 1 Humic substances form a series of relatively high-molecular-weight, brown-to-black-coloured substances
formed by secondary synthesis reactions.
NOTE 2 The term is used as a generic name to describe coloured material or its fractions (e.g. humic and fulvic acids)
obtained on the basis of solubility characteristics.
3.3
humic acid
HA
fraction of a humic substance that is not soluble in water under acidic conditions (pH <1 to 2) but is soluble at
higher pH values
NOTE Humic acids are dark brown to black in colour.
3.4
fulvic acid
FA
fraction of a humic substance that is soluble in water under all pH conditions
NOTE 1 Fulvic acids remain in solution after removal of humic acid by acidification.
NOTE 2 Fulvic acids are light yellow to yellow-brown in colour.
3.5
hydrophilic organic carbon
Hy
organic carbon compound consisting of non-humic and humic-like substances
NOTE In this part of ISO 12782, Hy is essentially regarded as the extractable organic carbon fraction that is not
identified as humic acid, fulvic acid or hydrophobic neutral organic carbon in accordance with the procedure specified in
Clause 8. Hydrophilic organic carbon generally consists of molecules with a lower molecular weight and higher COOH/C
ratios than humic acids and fulvic acids. Examples of compounds are: oxidized carbohydrates with carboxylic acid groups,
low-molecular-weight carboxylic acids, and sugar phosphates.
3.6
hydrophobic neutral organic carbon
HON
difference between the amount of adsorbed fulvic acid and hydrophilic organic carbon and the amount of
desorbed fulvic acid
NOTE Hydrophobic neutral organic carbon can include non-humic and humic-like compounds.
3.7
laboratory sample
sample intended for laboratory inspection or testing
[ISO 11074:2005]
2 © ISO 2012 – All rights reserved

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SIST EN ISO 12782-4:2013
ISO 12782-4:2012(E)
3.8
test sample
sample, prepared from the laboratory sample, from which the test portions are removed for testing or for
analysis; this portion of material, resulting from the laboratory sample by means of an appropriate method of
sample pretreatment, and having the size (volume/mass) necessary for the desired testing or analysis
NOTE Adapted from ISO 11074:2005.
3.9
test portion
analytical portion
quantity of material, of proper size, for measurement of the concentration or other property of interest, removed
from the test sample
NOTE 1 The test portion may be taken from the primary sample or from the laboratory sample directly if no preparation
of sample is required (e.g. with liquids), but usually it is taken from the prepared test sample.
NOTE 2 A unit or increment of proper homogeneity, size, and fineness, needing no further preparation, may be a test portion.
[ISO 11074:2005]
3.10
soil material
excavated soil, dredged material, manufactured soil, treated soil and fill material and other relevant materials,
including soil amendments and waste materials
4 Principle
Specific dissolved organic carbon species are isolated based on defined operational conditions. Humic acids
are precipitated at pH 1 and fulvic acids (and the hydrophobic organic neutral fraction) are adsorbed onto
DAX-8 resin. The organics remaining in solution after resin addition are classified as hydrophilic organic
substances. The DOC concentrations are measured after every step, from which the total individual
concentrations of humic and fulvic acids, hydrophobic organic neutrals, and hydrophilic organic substances,
are calculated.
5 Apparatus
The following apparatus shall be used. All materials that come into contact with the sample (material or reagents)
should not contaminate the compounds to be determined or adsorb the compounds of interest.
5.1 Balance, with an accuracy of 0,1 g.
5.2 Usual laboratory glass or plastic ware, rinsed in accordance with ISO 5667-3.
5.3 pH-meter with a measurement accuracy of at least ±0,05 pH units.
-1 -1
5.4 End-over-end shaking machine (5 min to 10 min ).
NOTE Other shaking methods can be used provided they can be shown to provide equivalent results.
5.5 Filtration apparatus, either a vacuum filtration device (between 2,5 kPa and 4,0 kPa) or a high-pressure
filtration apparatus (<0,5 MPa). Cleaning is compulsory.
5.6 Filters, pore size 20 µm, for use in the Büchner-funnel filtration device (5.7).
5.7 Büchner-funnel filtration device.
© ISO 2012 – All rights reserved 3

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SIST EN ISO 12782-4:2013
ISO 12782-4:2012(E)
5.8 Membrane filters, for the filtration device, fabricated from inert material with a pore size of 0,45 µm.
Filters shall be pre-washed with demineralized water in order to remove DOC.
5.9 Soxhlet extraction device.
5.10 Soxhlet extraction thimbles, glass-fibre extraction thimbles for the Soxhlet extraction device (5.9).
5.11 Centrifuge, preferably at 3 000g. For other appropriate conditions, see Annex C.
5.12 Centrifuge bottles, e.g. polycarbonate, of appropriate size, rinsed in accordance with ISO 5667-3.
5.13 Crushing equipment: jaw crusher or cutting device.
NOTE Due to crushing, contamination of the sample may occur to an extent which affects the leaching of some
constituents of concern, e.g. cobalt and tungsten from tungsten carbide equipment, or chromium, nickel and molybdenum
from stainless-steel equipment.
5.14 Sieving equipment, with a nominal screen size of 2 mm or 4 mm.
NOTE Due to sieving, contamination of the sample may occur to an extent which affects the leaching of some
constituents of concern e.g. cobalt and tungsten from tungsten carbide equipment, or chromium, nickel and molybdenum
from stainless-steel equipment.
5.15 Sample splitter, for sub-sampling of laboratory samples (optional).
6 Reagents
The reagents used shall be of analytical grade and the water used shall comply with grade 3 in accordance
with ISO 3696.
6.1 Demineralized water, deionized water or water of equivalent purity (5 < pH < 7,5) with a conductivity
< 0,5 mS/m according to grade 3 specified in ISO 3696.
6.2 Potassium hydroxide, c(KOH) = 0,1 mol/l and 1 mol/l.
6.3 Hydrochloric acid, c(HCl) = 0,1 mol/l to 6 mol/l.
6.4 Sodium hydroxide, c(NaOH) = 0,1 mol/l to 5 mol/l.
6.5 Acetonitrile, (CH CN), suitable for liquid chromatography.
3
6.6 Methanol, (CH OH), suitable for liquid chromatography.
3
1)
6.7 DAX-8 resin, e.g. Sigma-Aldrich .
NOTE Various documented methods for HS isolation and purification make use of XAD-8 resin to adsorb HA and/or
FA. This resin is no longer commercially available; therefore, the comparability of the substitute resin DAX-8 was tested.
See Annex B for information.
6.8 Nitric acid, c(HNO ) = 0,1 mol/l.
3
1) DAX-8 resin from Sigma-Aldrich is an example of a suitable product available commercially. This information is given
for the convenience of users of this document and does not constitute an endorsement by ISO of this product.
4 © ISO 2012 – All rights reserved

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SIST EN ISO 12782-4:2013
ISO 12782-4:2012(E)
7 Sample pretreatment
7.1 Sample size
The laboratory sample shall consist of a mass equivalent to at least 1 kg of dry mass. Perform sampling in
accordance with ISO 10381-1 in order to obtain a representative laboratory sample.
Sampling shal
...

SLOVENSKI STANDARD
oSIST prEN ISO 12782-4:2011
01-april-2011
[Not translated]
Soil quality - Parameters for geochemical modelling of leaching and specification of
constituents in soils and materials - Part 4: Extraction of humic substances from solid
samples (ISO/DIS 12782-4:2010)
Bodenbeschaffenheit - Parameter zur geochemischen Modellierung der Elution und
Speziation von Bestandteilen in Böden und Materialien - Teil 4: Extraktion von
Humusstoffen aus Feststoffproben (ISO/DIS 12782-4:2010)
Qualité du sol - Paramètres pour la modélisation géochimique du lessivage et
spécifications des constituants des sols et des matériaux - Partie 4: Extraction des
substances humiques des échantillons de sol (ISO/DIS 12782-4:2010)
Ta slovenski standard je istoveten z: prEN ISO 12782-4
ICS:
13.080.10 .HPLMVNH]QDþLOQRVWLWDO Chemical characteristics of
soils
oSIST prEN ISO 12782-4:2011 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN ISO 12782-4:2011

---------------------- Page: 2 ----------------------
oSIST prEN ISO 12782-4:2011


EUROPEAN STANDARD
DRAFT
prEN ISO 12782-4
NORME EUROPÉENNE

EUROPÄISCHE NORM

December 2010
ICS 13.080.05
English Version
Soil quality - Parameters for geochemical modelling of leaching
and specification of constituents in soils and materials - Part 4:
Extraction of humic substances from solid samples (ISO/DIS
12782-4:2010)
Qualité du sol - Paramètres pour la modélisation Bodenbeschaffenheit - Parameter zur geochemischen
géochimique du lessivage et spécifications des Modellierung der Elution und Speziation von Bestandteilen
constituants des sols et des matériaux - Partie 4: Extraction in Böden und Materialien - Teil 4: Extraktion von
des substances humiques des échantillons de sol (ISO/DIS Humusstoffen aus Feststoffproben (ISO/DIS 12782-4:2010)
12782-4:2010)
This draft European Standard is submitted to CEN members for parallel enquiry. It has been drawn up by the Technical Committee
CEN/TC 345.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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
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CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
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Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
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Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2010 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN ISO 12782-4:2010: E
worldwide for CEN national Members.

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oSIST prEN ISO 12782-4:2011
prEN ISO 12782-4:2010 (E)
Contents Page
Foreword .3

2

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oSIST prEN ISO 12782-4:2011
prEN ISO 12782-4:2010 (E)
Foreword
This document (prEN ISO 12782-4:2010) has been prepared by Technical Committee ISO/TC 190 "Soil
quality" in collaboration with Technical Committee CEN/TC 345 “Characterization of soils” the secretariat of
which is held by NEN.
This document is currently submitted to the parallel Enquiry.
Endorsement notice
The text of ISO/DIS 12782-4:2010 has been approved by CEN as a prEN ISO 12782-4:2010 without any
modification.

3

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oSIST prEN ISO 12782-4:2011

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oSIST prEN ISO 12782-4:2011
DRAFT INTERNATIONAL STANDARD ISO/DIS 12782-4
ISO/TC 190/SC 7 Secretariat: DIN
Voting begins on: Voting terminates on:
2010-12-02 2011-05-02
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION
Soil quality — Parameters for geochemical modelling of leaching
and specification of constituents in soils and materials —
Part 4:
Extraction of humic substances from solid samples
Qualité du sol — Paramètres pour la modélisation géochimique du lessivage et spécifications des constituants
des sols et des matériaux —
Partie 4: Extraction des substances humiques des échantillons de sol
ICS 13.080.05

ISO/CEN PARALLEL PROCESSING
This draft has been developed within the International Organization for Standardization (ISO), and
processed under the ISO-lead mode of collaboration as defined in the Vienna Agreement.
This draft is hereby submitted to the ISO member bodies and to the CEN member bodies for a parallel
five-month enquiry.
Should this draft be accepted, a final draft, established on the basis of comments received, will be
submitted to a parallel two-month approval vote in ISO and formal vote in CEN.
In accordance with the provisions of Council Resolution 15/1993 this document is circulated in
the English language only.
Conformément aux dispositions de la Résolution du Conseil 15/1993, ce document est distribué
en version anglaise seulement.
To expedite distribution, this document is circulated as received from the committee secretariat.
ISO Central Secretariat work of editing and text composition will be undertaken at publication
stage.
Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du
secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au
Secrétariat central de l'ISO au stade de publication.
THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE
REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN NATIONAL REGULATIONS.
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 SUPPORTING DOCUMENTATION.
©
International Organization for Standardization, 2010

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oSIST prEN ISO 12782-4:2011
ISO/DIS 12782-4
PDF disclaimer
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©
ii ISO 2010 – All rights reserved

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oSIST prEN ISO 12782-4:2011
ISO/DIS 12782-4
Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .1
4 Principle.3
5 Apparatus.3
6 Reagents.4
7 Sample pre-treatment.4
7.1 Sample size.4
7.2 Particle size reduction.5
7.2.1 General.5
7.2.2 Particle size reduction of soil.5
7.2.3 Particle size reduction of waste.5
7.3 Determination of dry residue.5
7.4 Test portion.6
8 Procedure.6
8.1 Preparation of DAX-8 resin.6
8.2 Determination of total HA, FA and Hy content in solid source materials.6
9 Eluate treatment, storage and analysis.7
10 Analytical determination.7
11 Blank test.7
12 Calculation.7
12.1 General correction factors for the calculations of HA, FA, Hy and HON in solid samples .7
12.2 Concentration of total HA, FA, Hy and HON concentrations in solid samples.8
13 Expression of results.11
14 Precision.11
15 Test report.11
16 Performance characteristics.11
Annex A (informative) Schematic representation of the fractionation procedure .12
Annex B (informative) Validation of procedure.13
B.1 Notes on the use of cleaned DAX-8.13
B.2 Preliminary investigations of DAX-8 and XAD-8 performance .13
B.3 Concentration dependent precipitation behaviour of HA. .14
B.4 Chemical characterization of HA precipitates obtained at different concentrations .15
Annex C (informative) Conditions regarding centrifugation .17
C.1 General.17
C.2 Example for calculation.17
Bibliography.20

© ISO 2010 – All rights reserved iii

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oSIST prEN ISO 12782-4:2011
ISO/DIS 12782-4
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 12782-4 was prepared by Technical Committee ISO/TC 190, Soil quality, Subcommittee SC 7, Soil and
site assessment.
ISO 12782 consists of the following parts, under the general title Soil quality — Parameters for geochemical
modelling of the leaching and speciation of constituents in soils and materials:
⎯ Part 1: Extraction of iron(hydr)oxides with ascorbic acid
⎯ Part 2: Extraction of iron(hydr)oxides with dithionite
⎯ Part 3: Extraction of aluminium(hydr)oxides with ammonium oxalate - oxalic acid
⎯ Part 4: Extraction of humic substances from solid samples
⎯ Part 5: Extraction of humic substances from aqueous samples
iv © ISO 2010 – All rights reserved

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oSIST prEN ISO 12782-4:2011
ISO/DIS 12782-4
Introduction
In addition to leaching procedures for subsequent chemical and ecotoxicological testing of soil and materials,
predictive models are becoming indispensable tools in the environmental risk assessment of these materials.
Models are particularly required when the results of laboratory leaching tests are to be translated to specific
scenarios in the field, with regard to assessing risks of both contaminant migration and bioavailability.
In the past few years, geochemical models have been shown to be valuable tools to be combined with the
data obtained from characterisation leaching standards such as the pH-dependence and percolation tests.
These models have the advantage of being based on fundamental thermodynamical parameters that have a
general validity. In order to enable extrapolation of laboratory leaching data to the mobility and/or
bioavailability of a constituent in a specific field scenario, these models require additional input parameters for
specific soil properties (Figure 1).

Key
4 dissolved humic substances
1 experiment
5 reactive (solid) surfaces
2 geochemical speciation modelling
6 database with stability constants
3 available metal concentration
7 computer program
8 assumptions
Figure 1 — elationships between experimental data, as obtained from laboratory leaching/extraction
tests, and geochemical modelling of the speciation of a heavy metal in the environment (modified after
M. Gfeller & R. Schulin, ETH, Zürich
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oSIST prEN ISO 12782-4:2011
ISO/DIS 12782-4
The characterisation leaching standards provide information on the concentrations of the contaminant of
interest as a function of, in particular, pH and liquid/solid (L/S) ratio. In addition, a more complete analysis of
the leachates does also provide information on the major ion composition and dissolved organic carbon
(DOC), parameters that are particularly important for the chemical speciation of constituents through
processes such as precipitation, complexation and competition for adsorption on reactive mineral and organic
surfaces in the soil. As Figure 1 shows, for the example of copper, geochemical modelling allows calculation
of the distribution of the metal among these different chemical species in the system of interest, which is
necessary information for risk assessment purposes as these different chemical forms play distinct roles in the
mobility and bioavailability of the metal in the soil. In addition to information obtained from the leaching
standards (in their current state of development/definition), two additional types of information are required:
1) the “available” (sometimes also referred to as “active” or “exchangeable”) concentration of the
constituent in the solid phase, as opposed to the total concentration determined by acid destruction
of the soil matrix. This “available” concentration can be obtained by leaching at low pH, a condition
that can be obtained by extending the pH range in the pH-dependence leaching test (ISO/TS 21268-
4) down to pH of approximately 0,4.
2) the concentration of reactive organic and mineral surfaces in the soil, which constitute the major
binding (adsorption) sites for most constituents in the soil matrix.
The major reactive surfaces that control the binding of constituents by sorption processes to the soil matrix are
particulate organic matter and iron- and aluminium(hydr)oxides. It is generally accepted that the reactivity of
these mineral and organic surfaces can strongly vary as a function of their specific surface area/crystallinity
(iron- and aluminium(hydr)oxides) and composition (organic matter). When intending to use the results for the
above described purposes of geochemical modelling in conjunction with leaching tests, it is important that the
methods are selective for reactive surfaces for which also generic thermodynamical adsorption parameters
are available for the most important major and trace elements.
These reactive surfaces have been identified in soils as well as in a variety of other materials for which the
leaching of constituents is of relevance. It has been shown that the binding properties of these surfaces play a
generic role in the speciation and leaching of constituents among these different materials. As an example, a
similar geochemical modelling approach, using model input from the partial or complete ISO 12782 series,
has been successfully applied to different soils [1], amended soils [2,3], municipal incinerator bottom ash [4],
steel slag [5, 6], bauxite residues [7], and recycled concrete aggregate [8]. Hence, the scope of the ISO 12782
series extends from soils to materials including soil amendments and waste materials.
This part of ISO 12782 aims to determine important reactive organic surfaces in soil and materials, for which
generic thermodynamic adsorption parameters exist, i.e., humic and fulvic acids. The procedure is based on
[9], while generic thermodynamic adsorption parameters for humic and fulvic acids are available in [10, 11].
Thermodynamic parameters for other adsorption models than used in [10, 11] are also available in the
literature and may also be used to model the binding of constituents to humic and fulvic acids.
The method [12] is based on a conventional isolation and purification method [9] that is also used by the
International Humic Substances Society (IHSS).


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oSIST prEN ISO 12782-4:2011
DRAFT INTERNATIONAL STANDARD ISO/DIS 12782-4

1 Scope
This part of ISO 12782 specifies a procedure to determine the concentration of humic substances in soil or
materials. Materials also include waste as given in the Introduction.
NOTE The content of humic substances can be used as input in geochemical models.
2 Normative references
The following referenced documents are indispensable for the application 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 5667-3, Water quality – Sampling – Part 3: Guidance on the preservation and handling of samples.
ISO 8245, Water quality — Guidelines for the determination of total organic carbon (TOC) and dissolved
organic carbon (DOC).
ISO 10381-1, Soil quality — Sampling — Part 1: Guidance on the design of sampling programmes
ISO 10381-2, Soil quality — Sampling — Part 2: Guidance on sampling techniques
ISO 10381-3, Soil quality — Sampling — Part 3: Guidance on safety
ISO 10381-4, Soil quality — Sampling — Part 4: Guidance on the procedure for investigation of natural, near-
natural and cultivated sites
ISO 10381-5, Soil quality — Sampling — Part 5: Guidance on investigation of soil contamination of urban and
industrial sites
ISO 10381-6, Soil quality — Sampling — Part 6: Guidance on the collection, handling and storage of soil for
the assessment of aerobic microbial processes in the laboratory
ISO 11074:2005, Soil quality - Vocabulary .
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.
3.1
dissolved organic carbon
DOC
sum of organically bound carbon present in water originating from compounds (including cyanate and
thiocyanate) which will pass a membrane filter of pore size of 0,45 µm
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oSIST prEN ISO 12782-4:2011
ISO/DIS 12782-4
3.2
humic substances
HS
(partial) decomposition products from plant and animal tissue
NOTE 1 Humic substances form a series of relatively high-molecular-weight, brown to black coloured substances
formed by secondary synthesis reactions.
NOTE 2 The term is used as a generic name to describe coloured material or its fractions (e.g. humic and fulvic acids)
obtained on the basis of solubility characteristics.
3.3
humic acids
HA
fraction of humic substances that is not soluble in water under acidic conditions (pH <1 to 2) but is soluble at
higher pH values
NOTE Humic acids are dark brown to black in colour.
3.4
fulvic acids
FA
fraction of humic substances that is soluble in water under all pH conditions
NOTE 1 Fulvic acids remain in solution after removal of humic acid by acidification.
NOTE 2 Fulvic acids are light yellow to yellow-brown in color.
3.5
hydrophilic organic carbon
Hy
organic carbon compound consisting of non-humic and humic-like substances
NOTE In this part of ISO 12782, Hy is essentially considered as the extractable organic carbon fraction that is not
identified as HA, FA or HON according to the procedure specified in Clause 7. Hydrophilic organic carbon generally
consists of molecules with a lower molecular weight and higher COOH/C ratios, compared to HA and FA. Examples of
compounds are: oxidized carbohydrates with carboxylic acid groups, low molecular weight carboxylic acids, and sugar
phosphates.
3.6
hydrophobic neutral organic carbon
HON
difference between the amount of adsorbed FA + HON and the amount of desorbed FA
NOTE Hydrophobic neutral organic carbon can include non-humic and humic-like compounds.
3.7
laboratory sample
sample intended for laboratory inspection or testing
[ISO 11074:2005]
3.8
test sample
sample, prepared from the laboratory sample, from which the test portions are removed for testing or for
analysis. This portion of material, resulting from the laboratory sample by means of an appropriate method of
sample pre-treatment, and having the size (volume/mass) necessary for the desired testing or analysis
[ISO 11074:2005]
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oSIST prEN ISO 12782-4:2011
ISO/DIS 12782-4
3.9
test portion
analytical portion
quantity of material, of proper size, for measurement of the concentration or other property of interest,
removed from the test sample
NOTE 1 The test portion may be taken from the primary sample or from the laboratory sample directly if no preparation
of sample is required (e.g. with liquids), but usually it is taken from the prepared test sample.
NOTE 2 A unit or increment of proper homogeneity, size, and fineness, needing no further preparation, may be a test
portion.
[ISO 11074:2005]
3.10
soil material
excavated soil, dredged material, manufactured soil, treated soil and fill material and other relevant materials,
including soil amendments and waste materials.
4 Principle
Specific dissolved organic carbon species are isolated based on defined operational conditions. Humic acids
are precipitated at pH 1 and fulvic acids (and the hydrophobic organic neutral fraction) are adsorbed onto
DAX-8 resin. The organics remaining in solution after resin addition are classified as hydrophilic organic
substances. The DOC concentrations are measured after every step, from which the total individual
concentrations of humic and fulvic acids, hydrophobic organic neutrals, and hydrophilic organic substances,
are calculated.
5 Apparatus
The following equipment shall be used. All materials that come in contact with the sample (material or
reagents) should not cause contamination by compounds to be determined or adsorb the compounds of
interest.
5.1 Balance with an accuracy of 0,1 g.
5.2 Appropriate general laboratory glass or plastic ware, cleaned with distilled and demineralised water
and diluted acid (HNO ) (6.8) before use.
3
5.3 pH meter with a measurement accuracy of at least ± 0,05 pH units.
-1 -1
5.4 End over end shaking machine (5 min to 10 min )
NOTE Other shaking methods can be used provided that they can be shown to provide equivalent results.
5.5 Filtration apparatus, either a vacuum filtration device (between 2,5 kPa to 4,0 kPa) or a high pressure
filtration apparatus (< 0,5 MPa). Cleaning is compulsory.
5.6 Filters, pore size 20 µm for use in the Buchner funnel filtration device (5.7).
5.7 Buchner funnel filtration device
5.8 Membrane filters for the filtration device, fabricated from inert material with a pore size of 0,45 µm.
Filters shall be pre-washed with demineralized water in order to remove DOC.
5.9 Soxhlet extraction device
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oSIST prEN ISO 12782-4:2011
ISO/DIS 12782-4
5.10 Soxhlet extraction thimbles, glassfibre ext
...

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