prEN ISO 15799

Soil quality - Guidance on the ecotoxicological characterization of soils and soil materials (ISO 15799:2019)

This document is one of a family of International Standards providing guidance on soils and soil materials in relation to certain functions and uses including conservation of biodiversity. It applies in conjunction with these other standards. It provides guidance on the selection of experimental methods for the assessment of the ecotoxic potential of soils and soil materials (e.g. excavated and remediated soils, refills, embankments) with respect to their intended use and possible adverse effects on aquatic and soil dwelling organisms.
NOTE       This is a reflection of the maintenance of the habitat and retention function of the soil. In fact, the methods listed in this document are suitable for usage in a TRIAD approach, i.e. for an ecological assessment of potentially contaminated soils (see ISO 19204).
This document does not cover tests for bioaccumulation.
The ecological assessment of uncontaminated soils with a view to natural, agricultural or horticultural use is not within the scope of this document. Such soils can be of interest if they can serve as a reference for the assessment of soils from contaminated sites.
The interpretation of results gained by applying the proposed methods is not in the scope of this document.

Bodenbeschaffenheit - Anleitung zur ökotoxikologischen Charakterisierung von Böden und Bodenmaterialien (ISO 15799:2019)

Dieses Dokument gehört zu einer Familie von Internationalen Normen, die Anleitungen zur Charakterisierung von Böden und Bodenmaterial mit Bezug zu bestimmten Funktionen und Nutzungen enthalten, einschließlich Erhalt der Biodiversität. Es gilt in Verbindung mit diesen anderen Normen. Es enthält eine Anleitung für die Auswahl der Untersuchungsverfahren zur Bestimmung des ökotoxikologischen Potenzials von Böden und Bodenmaterial (z. B. Bodenaushub, saniertes Bodenmaterial, Verfüllmaterial, Aufschüttungen) mit Berücksichtigung ihrer vorgesehenen Nutzung sowie möglicher schädlicher Wirkungen auf aquatische Lebewesen und Bodenlebewesen.
ANMERKUNG   Dies ist ein Abbild der Wirksamkeit der Lebensraum- und Rückhaltefunktion. Tatsächlich sind die in diesem Dokument aufgeführten Verfahren für die Verwendung mit einem TRIAD-Ansatz geeignet, d. h. für eine ökologische Bewertung potentiell kontaminierter Böden (siehe ISO 19204).
Dieses Dokument enthält keine Prüfverfahren zur Bestimmung der Bioakkumulation.
Dieses Dokument ist nicht für die ökologische Bewertung von nicht verunreinigten Böden mit naturnaher, landwirtschaftlicher oder forstwirtschaftlicher Nutzung anwendbar. Solche Böden können jedoch von Interesse als Referenzböden für die Bewertung von Böden aus verunreinigten Standorten sein.
Die Auswertung von Ergebnissen, die nach den vorgeschlagenen Verfahren erhalten werden, ist nicht Gegenstand dieses Dokuments.

Qualité du sol - Lignes directrices relatives à la caractérisation écotoxicologique des sols et des matériaux du sol (ISO 15799:2019)

Le présent document fait partie d'une famille de Normes internationales fournissant des lignes directrices sur les sols et les matériaux du sol en relation avec certaines fonctions et utilisations, y compris la préservation de la biodiversité. Il s'applique conjointement avec ces autres normes. Il fournit des lignes directrices relatives à la sélection des méthodes expérimentales permettant l'évaluation du potentiel écotoxique des sols et des matériaux du sol (par exemple terres excavées ayant fait l'objet d'une remédiation, remblais, talus) par rapport à leur utilisation prévue et aux effets éventuellement défavorables pour les organismes vivant dans l'eau et le sol.
NOTE       Il est le reflet du maintien des fonctions d'habitat et de rétention du sol. En fait, les méthodes énumérées dans le présent document sont adaptées à une utilisation dans l'approche TRIADE, c'est-à-dire pour une évaluation écologique des sols potentiellement contaminés (voir l'ISO 19204).
Le présent document ne traite pas des essais relatifs à la bioaccumulation.
L'évaluation écologique des sols non pollués en vue d'une utilisation naturelle, agricole ou horticole ne relève pas du domaine d'application du présent document. De tels sols peuvent être intéressants s'ils peuvent servir de référence pour l'évaluation de sols provenant de sites pollués.
L'interprétation des résultats obtenus selon les méthodes proposées ne relève pas du domaine d'application du présent document.

Kakovost tal - Navodilo za ekotoksikološko karakterizacijo tal in talnih materialov (ISO 15799:2019)

General Information

• Status: Not Published
• ICS: 13.080.99 - Other standards related to soil quality
• Technical Committee: CEN/TC 444 - Environmental characterization
• Drafting Committee: CEN/TC 444/WG 4 - Biological characterization
• Ref Project: oSIST prEN ISO 15799:2022 - Soil quality - Guidance on the ecotoxicological characterization of soils and soil materials (ISO 15799:2019)

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN ISO 15799:2022
01-julij-2022

Kakovost tal - Navodilo za ekotoksikološko karakterizacijo tal in talnih materialov

(ISO 15799:2019)

Soil quality - Guidance on the ecotoxicological characterization of soils and soil materials

(ISO 15799:2019)

Qualité du sol - Lignes directrices relatives à la caractérisation écotoxicologique des sols

et des matériaux du sol (ISO 15799:2019)
Ta slovenski standard je istoveten z: prEN ISO 15799
ICS:
13.080.99 Drugi standardi v zvezi s Other standards related to
kakovostjo tal soil quality
oSIST prEN ISO 15799:2022 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 15799:2022
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oSIST prEN ISO 15799:2022
INTERNATIONAL ISO
STANDARD 15799
Second edition
2019-03
Soil quality — Guidance on the
ecotoxicological characterization of
soils and soil materials
Qualité du sol — Lignes directrices relatives à la caractérisation
écotoxicologique des sols et des matériaux du sol
Reference number
ISO 15799:2019(E)
ISO 2019
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oSIST prEN ISO 15799:2022
ISO 15799:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© 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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
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oSIST prEN ISO 15799:2022
ISO 15799:2019(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Field of application ............................................................................................................................................................................................ 3

4.1 Soils and areas of soil use where ecotoxicity tests should be considered ........................................... 3

4.2 Soils and areas of soil use where ecotoxicological tests are not necessary ........................................ 3

5 Selection of tests according to the use/re-use of soils and soil materials and soil

functions ....................................................................................................................................................................................................................... 4

5.1 Use of ecotoxicity tests ..................................................................................................................................................................... 4

5.2 General criteria for selection of tests ................................................................................................................................... 4

5.3 Considerations for the examination of soil functions ............................................................................................ 5

5.3.1 Retention function .......................................................................................................................................................... 5

5.3.2 Habitat function ................................................................................................................................................................ 5

6 Sampling, transport, storage and sample preparation ................................................................................................ 7

7 Limitations of proposed biotests for soils/soil materials ......................................................................................... 8

Annex A (informative) Standardized forms of recommended test systems ................................................................9

Bibliography .............................................................................................................................................................................................................................47

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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 4,

Biological characterization.

This second edition cancels and replaces the first edition (ISO 15799:2003), which has been technically

revised. The main changes compared to the previous edition are as follows:

— standardized forms of recommended test systems in Annex A have been amended and updated (e.g.

ISO 20963 deleted and ISO 18311, ISO 18187 added).

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.
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Introduction

Most of the existing ecotoxicological test methods (biotests) that are being internationally harmonized

were developed to describe the ecotoxic potential of a test substance when added to a soil/soil material.

These methods can be used with some modifications for the ecotoxicological characterization of soils

and soil materials with respect to their function depending on the intended use. For substances with

properties resulting in toxic effects, biotests are a complement to conventional chemical analysis.

Results from chemical analysis can be used for ecotoxicological assessments based on information on

the substances identified, including properties of the chemicals, e.g. their bioaccumulation potential.

This information is often scarce (if it exists at all) and it does not include possible interactions (synergy/

antagonism) between chemicals and the complex soil matrix. Furthermore, an exhaustive identification

and quantification of substances is impractical. Therefore, ecotoxicological testing of soils can be used

for investigating the potential toxicity of complex chemical mixtures. The extrapolation from laboratory

tests to field conditions requires adequate consideration of important environmental factors within the

test conditions and the selection of suitable ecotoxicological end points.
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oSIST prEN ISO 15799:2022
INTERNATIONAL STANDARD ISO 15799:2019(E)
Soil quality — Guidance on the ecotoxicological
characterization of soils and soil materials
1 Scope

This document is one of a family of International Standards providing guidance on soils and soil

materials in relation to certain functions and uses including conservation of biodiversity. It applies in

conjunction with these other standards. It provides guidance on the selection of experimental methods

for the assessment of the ecotoxic potential of soils and soil materials (e.g. excavated and remediated

soils, refills, embankments) with respect to their intended use and possible adverse effects on aquatic

and soil dwelling organisms.

NOTE This is a reflection of the maintenance of the habitat and retention function of the soil. In fact, the

methods listed in this document are suitable for usage in a TRIAD approach, i.e. for an ecological assessment of

potentially contaminated soils (see ISO 19204).
This document does not cover tests for bioaccumulation.

The ecological assessment of uncontaminated soils with a view to natural, agricultural or horticultural

use is not within the scope of this document. Such soils can be of interest if they can serve as a reference

for the assessment of soils from contaminated sites.

The interpretation of results gained by applying the proposed methods is not in the scope of this

document.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain 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 Types of soil and other soil materials
3.1.1
soil

upper layer of the Earth’s crust composed of mineral particles, organic matter, water, air and organisms

[SOURCE: ISO 11074:2015, 2.1.11, modified — The definition has been slightly modified and the Note 1

to entry has been deleted.]
3.1.2
soil material

material which includes excavated soil (3.1.3), dredged materials, manufactured soils, treated soils and

fill materials
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3.1.3
excavated soil

any natural material excavated from ground including top-soil, sub-soil, altered parent rock and parent

rock itself
Note 1 to entry: Excavated soil typically arises during construction works.
[SOURCE: ISO 15176:2002, 3.1.5]
3.1.4
standard soil

field collected soil whose main properties (e.g. pH, texture, organic matter content) are within a

known range

Note 1 to entry: An example for standard soils is “Eurosoils” (see Reference [28]).

3.2 Terms relating to soil characteristics
3.2.1
habitat function

ability of soils (3.1.1)/soil materials (3.1.2) to serve as a habitat for microorganisms, plants, soil living

animals and their interactions (biocenoses)
3.2.2
retention function

ability of soils (3.1.1)/soil materials (3.1.2) to adsorb pollutants (3.2.3) in such a way that they cannot be

mobilised via the water pathway and translocated into the food chain

Note 1 to entry: The habitat and retention functions include the following soil functions according to

ISO 11074:2015:
— control of substance and energy cycles as components of ecosystems;
— basis for the life of plants, animals and man;
— carrier of genetic reservoir;
— basis for the production of agricultural products;

— buffer inhibiting movement of water, contaminants or other agents into the ground water.

3.2.3
pollutant

substance which due to their properties, amount or concentration cause impacts on the soil function or

soil use

Note 1 to entry: See also contaminant (3.2.4) and potentially harmful substance (3.2.5).

[SOURCE: ISO 11074:2015, 3.4.18, modified — Wording has been slightly modified and Note 1 to entry

has been added.]
3.2.4
contaminant
substance or agent present in the soil (3.1.1) as a result of human activity

Note 1 to entry: There is no assumption in this definition that harm results from the presence of the contaminant:

see also pollutant (3.2.3) and potentially harmful substance (3.2.5).

[SOURCE: ISO 15176:2002, definition 3.2.6, modified — The wording in the Note 1 to entry has been

slightly modified.]
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3.2.5
potentially harmful substance

substance which when present in sufficient concentration or amount may be harmful to humans or the

environment

Note 1 to entry: It may be the result of human activity [contaminant (3.2.4)] or naturally occurring.

[SOURCE: ISO 15176:2002, 3.2.8, modified — A Note 1 to entry has been added.]
3.3 Land and sites
3.3.1
re-use
useful and harmless utilisation of soil materials

Note 1 to entry: In the context of this International Standard, re-use means the transfer of soil materials to

another location for use in agriculture, horticulture, forestry, gardens, recreational areas and construction sites.

[SOURCE: ISO 15176:2002, 3.4.1]
4 Field of application
4.1 Soils and areas of soil use where ecotoxicity tests should be considered

Ecotoxicity tests should be considered in the following soils and areas of soil use:

— Assessment of the ability of a soil to sustain a natural biocenosis or agriculture.

— Assessment of the combined ecotoxicity of all bioavailable contaminants present in soils or soil

materials.

— Assessment of the ecotoxicity of potentially harmful substances in cases where the soil/soil material

can affect the ground and surface water.

— Identification of soils or soil materials (refills, embankments) with a low degree of contamination

usually within a depth of 1 m, which can remain at the site without further treatment.

— Detection of potential ecotoxicity which could not be traced by chemical analysis.

— Monitoring and control of the success of soil treatment (off-site, on-site/in situ).

— Monitoring and control of soils/soil materials, which have been decontaminated and are to be

applied at the surface.
4.2 Soils and areas of soil use where ecotoxicological tests are not necessary

Provided that groundwater contamination can be excluded, ecotoxicological testing is not necessary in

the following cases.

— Contaminated soils which are classified as hazardous waste or can be characterized clearly by

chemical/analytical parameters. In such cases, ecotoxicological testing may be useful for a final

investigation after remediation and for process control during biological remediation.

— Commercially/industrially used areas with no prospect of horticultural/agricultural use.

— Soil materials or backfilled materials in an area which is to be effectively sealed by covering with

buildings or other forms of low permeability cover such as concrete or tarmacadam or asphalt.

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5 Selection of tests according to the use/re-use of soils and soil materials and
soil functions
5.1 Use of ecotoxicity tests

Toxicants can affect different species (and in some cases genotypes) present within ecosystems at

different concentrations. The ideal approach for the precise ecotoxicological characterization of the soil

toxicity is to use a battery of tests with several species belonging to different taxonomic and trophic

groups to avoid false-negative results due to an adaption of a test system (genotypic shift) to a specific

contaminant as compared to uncontaminated soils. Studies using field or semi-field investigations are

rarely carried out and may be very expensive.

The ideal scheme can be rendered more practicable by the adoption of simpler testing strategies and

the application of safety factors to the results obtained. If, however, testing is performed on one species

or function only, the high diversity in the sensitivity of species to toxicants will result in a high level of

uncertainty. It is therefore recommended to test at least a microbial process, a species from the plant

kingdom, and one from the animal kingdom, usually a saprophagous/detritivorous species. If more than

one animal species are tested, a predatory species should be included in the test battery. The minimum

number of species to be tested depends on the regulations to which the test strategy shall comply. This

document only gives the basic principles for their use. Further considerations to the selection of tests

using soil organisms are given in 5.3.
5.2 General criteria for selection of tests

Criteria for the selection of ecotoxicity tests were established in the context of hazard assessment and

classification of chemicals. These criteria should also apply for the ecotoxicological characterization of

contaminated soils. Criteria reviewed were scientific validity, ecological significance, practicability and

acceptability (see References [27] and [28]).

Basic requirements which test protocols shall fulfil in order to be laid down in International Standards

include reproducibility, statistical validity, general acceptance and performance.

The importance of a criterion is relative to the specific situation. Decisions have to be made between

which criteria are most important or tests which may have to be modified by more practical

considerations, such as easy culturing of test organisms in the laboratory or the availability of life

stages required for a test throughout the year.

The test methods recommended (see Annex A) in this document were originally designed for hazard

assessment of chemicals and were in most cases internationally harmonized e.g. by OECD, EU or ISO. In

most of them provisions have been made to adapt the test design for the purposes within the scope of

this document. In addition, the selection of ecotoxicological test methods for the assessment of soils/soil

materials depends on their intended use/re-use and on the soil functions to be protected, in particular

the retention and habitat functions.
Table 1 gives an example of a decision scheme based on the relevant function.
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Table 1 — Relevance for ecotoxicological testing to the intended re-use of the soil

Re-use of soils Soil function
Retention function Habitat function
Aquatic organisms Plant growth Soil biocenoses
Detection of biological effects
Below sealed areas low low low
Commercially and industrially used un- high low low
sealed areas
Landfill covering high high low
Green areas, parks and recreation areas high high high
Areas used in horticulture or agriculture high high high
Applies only to the unsatured soil zone.
5.3 Considerations for the examination of soil functions
5.3.1 Retention function

Transport via water of soluble, colloidal or particle fractions play a dominant role in the risk assessment

of contaminated soils. This is true not only because water can mobilize contaminants, but also because

contaminants and metabolites in the water phase potentially have a severe effect on microorganisms,

plants and soil fauna.

Aqueous eluates (for preparation see Clause 6, ISO 18772, EN 14735) are useful for testing ecotoxic effects

on organisms exposed via the water mediated transport. It should be taken into account that substances

mobilized via water can be subjected to different types of changes, such as metabolism or hydrolysis when

transported into the groundwater and from there into surface waters, and that their concentrations are

reduced by dilution. Moreover, substances can be mobilised over time due to environmental changes (e.g.

pH, chemical and biological transformation). Eluates can serve as early indicators for the contamination

of pore and ground water prior to the exposure of surface and drinking water.

With these aspects, the investigation of groundwater and eluates is of utmost importance regardless of

the proposed soil use.

For ecotoxicology tests working with aqueous soil extracts and aquatic test organisms it shall be

considered that nutrient ions and compounds are easily dissolved in water (at least easier than

hydrophobic pollutants) and can substantially interfere during the test.
5.3.2 Habitat function
5.3.2.1 General

The suitability of the soil for living organisms can best be examined by means of test methods which are

selected to include organisms and processes representative of different taxonomic and ecological groups.

5.3.2.2 Soil material used as control for bioassays on solid matrices

As a general principle in ecotoxicological testing, any end point measured in a treatment is compared

with the one measured in the control(s).

In order to evaluate the suitability of the soil for soil-dwelling organisms, it is a prerequisite to compare

the contaminated soil or soil material with a control material, which may also be used for preparing

dilution series with the contaminated sample.
Several types of control material can be used:

— an uncontaminated soil with comparable pedological properties to the sample being tested;

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— an inert material (e.g. quartz sand);
— a certified natural soil (e.g. standard soil);
— a standardized artificial soil (see ISO 11268-1 and ISO 11268-2, ISO 11267).

The choice between these control materials depends entirely on the aims of the ecotoxicological

assessment, the type of biological test being carried out and the requirements of the test organism. This

recommendation cannot be generalized for all biological tests. Adding sand to a soil or a soil material can

create a compact mixture which is incompatible with the growth and development of many organisms

(e.g. plant growth tests). It is preferable to use a more complex control material (such as artificial soil)

for dilution where this would have the advantage of reproducing more closely the natural environment

of the organisms and even if it may interact with pollutants. Placing an organism in a medium which

does not match the most important characteristics of its natural habitat may cause stress.

— If a dose-response curve is needed, one of the control materials mentioned above may be used to

dilute the contaminated substrate.

— If the aim is to classify each sample of soil or soil materials in terms of ecotoxicity hazard, it is

preferable to use an inert material (e.g. quartz sand) which will not interact with the pollutants

present in the sample, and whose composition and granulometry can be rigorously standardized.

The requirements of the control material shall take into account the different soil uses and the type

and origin of the soil (e.g. undisturbed soil, refilling material, excavated soil, remediated soil). Nutrient

deficiency, as well as physical conditions, can cause differences in plant growth and animal behaviour

that need not necessarily be caused by the pollutant situation and the hazard potential.

— If the aim is to evaluate the ecotoxicity of a soil or soil material sample from a contaminated site, the

preferred method would be to use an uncontaminated control material that is similar to the sample

being tested.

— If the aim is to evaluate the ecotoxicity of soils or soil materials which may be re-employed for

certain specific uses, the preferred method would be to use as a control material any material which

may in future be mixed with soil or soil material.
5.3.2.3 Soil as substrate (medium) for soil microorganisms

The soil microflora comprises on average 80 % of the mass of organisms living in soil. In combination

with the microfauna, the main functions of the microflora are the decomposition and degradation of

complex organic substances to easily available nutrients thereby maintaining the natural substance

cycles of carbon, nitrogen, phosphorus and sulfur.

Substrate-induced respiration provides an indicator of the microbial population density.

Nitrifying bacteria, which are responsible for the oxidation of ammonium to nitrite and from nitrite to

nitrate, are a very sensitive group of microorganisms. Decreased nitrification need not necessarily lead

to significant changes in the ecosystem but can be used as a sensitive indicator for the inhibition of an

essential soil process.

The purpose of determining the microbial biomass or other microbial processes in soils is to allow

assessment of the continued maintenance of soil fertility, the potential ability to degrade organic

compounds, and the effects of added materials on the soil microbial community.
5.3.2.4 Soil as substrate for plant growth

After microorganisms, plant roots constitute the largest biological surface in soil. Their contact

area with soil particles is increased by the presence of root hairs and mycorrhizal associations (VA-

mycorrhiza with cultivated plants and additional ectomycorrhizal with woody plants).

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As with the other bioassays proposed, tests with higher plants are designed to assess the bioavailability

and effects of pollutants detected or not detected by chemical analysis respectively. By applying a test

period of at least 14 days, short-term changes in the soil by the test plant itself are included.

The accumulation of pollutants in plants, their metabolism and their effects on consumers are not

investigated in these tests. They do not apply to the assessment of soil fertility and productivity.

5.3.2.5 Soil as substrate for soil-inhabiting fauna
Soil animals generally fulfil the following four functions:
— mechanical activities (drainage, aeration, mixing, mechanical comminution);

— chemical changes (enhanced availability of nitrate and phosphate from excrements and accelerated

formation of clay-humus complexes, after the substrate has passed the gut);

— biological changes (distribution of microorganisms in the soil matrix, synergistic effects through

stimulation of microbial activity and organic matter decomposition);
— significant links in the food web.

Short-term and long term tests are available for examination of the effects of pollutants on soil

fauna. For testing the habitat function, characterization by sub-lethal test parameters is particularly

recommended.

Since a single test method cannot adequately represent the vast number of very diverse invertebrates, a

test battery should be used. When selecting the individual test species, the following criteria should be

considered:
— trophic level: e.g. saprophagous and predatory species should be included;

— taxonomic/physiological groups: in order to cover the biodiversity of soil communities, at least

representatives of Annelida and Arthropoda have to be selected;

— size class/exposure pathway: species of the micro-, meso- and macrofauna do not only represent

various size classes but also different life-styles and therefore exposure routes (e.g. pore water

versus food uptake);

— ecological role: at least soil-dwelling and litter-inhabiting species are important to be considered.

Only internationally standardized methods should be used.
6 Sampling, transport, storage and sample preparation

Before soil quality is assessed by any of the methods proposed, soil samples need to be collected from

the site under investigation (see ISO 23611-6). Soil sampling should be carried out by trained personnel

with sufficient knowledge of sampling, handling of samples and safety measures at contaminated sites

and sampling locations. The sampling strategy and handling should be determined by the site to be

investigated, the kind of contamination and the
...