SIST EN ISO 11266:2020

Soil quality - Guidance on laboratory testing for biodegradation of organic chemicals in soil under aerobic conditions (ISO 11266:1994)

Provides guidance on the selection and conduct of appropriate test methods for the determination of biodegradation of organic chemicals in aerobic soils. Does not describe any specific test method.

Bodenbeschaffenheit - Anleitung für Laboratoriumsuntersuchungen zur biologischen Abbaubarkeit von organischen Chemikalien im Boden unter aeroben Bedingungen (ISO 11266:1994)

Diese Internationale Norm enthält eine Anleitung für die Auswahl und Durchführung geeigneter Prüf-verfahren zur Bestimmung der biologischen Abbaubarkeit von organischen Chemikalien in Böden unter aeroben Bedingungen. Sie beschreibt kein spezifisches Prüfverfahren.

Qualité du sol - Lignes directrices relatives aux essais en laboratoire pour la biodégradation de produits chimiques organiques dans le sol sous conditions aérobies (ISO 11266:1994)

La présente Norme internationale fournit des lignes directrices sur le choix et la conduite de méthodes d'essai appropriées pour la détermination de la biodégradation de produits chimiques organiques dans des sols aérobies. Elle ne décrit aucune méthode d'essai spécifique.

Kakovost tal - Navodilo za laboratorijsko preskušanje biološke razgradljivosti organskih spojin v tleh pri aerobnih pogojih (ISO 11266:1994)

General Information

• Status: Published
• Public Enquiry End Date: 02-Feb-2020
• Publication Date: 23-Sep-2020
• ICS: 13.080.30 - Biological properties of soils
• Technical Committee: KAT - Soil quality
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 19-Aug-2020
• Due Date: 24-Oct-2020
• Completion Date: 24-Sep-2020
• Ref Project: EN ISO 11266:2020 - Soil quality - Guidance on laboratory testing for biodegradation of organic chemicals in soil under aerobic conditions (ISO 11266:1994)

Overview

SIST EN ISO 11266:2020 is a European and International Standard that provides guidance on laboratory testing for the biodegradation of organic chemicals in soil under aerobic conditions. Published by CEN and originally developed by ISO/TC 190, this standard assists laboratories and environmental professionals in selecting and conducting appropriate test methods to assess the biodegradability of organic compounds in aerobic soils. The document focuses on general guidelines and does not prescribe specific test methods.

Understanding the biodegradation of organic chemicals is vital for assessing soil quality and environmental safety. Biodegradation affects the persistence and potential toxicity of chemicals introduced into the soil through agricultural, industrial, or accidental activities. This standard aids in determining how quickly and extensively organic substances decompose under oxygen-rich conditions, ensuring accurate and reproducible laboratory evaluations.

Key Topics

Biodegradation Definitions

• Biodegradation: Molecular breakdown of organic substances by living organisms.
• Primary Biodegradation: Partial degradation that removes some key features of the parent compound.
• Ultimate Biodegradation: Complete breakdown into carbon dioxide, water, minerals, and microbial biomass.
• Persistence: The duration a chemical remains in soil.
• Disappearance Times (DT50, DT90): Times for the compound concentration to reduce by 50% or 90%, indicating degradation rate.
• Bound Residues: Non-extractable or chemically bound compounds in soil that resist removal.
• Mineralization: Final stage of degradation producing inorganic substances.

Soil and Test Material Considerations

• Selecting representative soil samples, ideally from the site of chemical contact.
• Detailed profiling of soil characteristics including particle size, pH, organic matter content, cation exchange capacity, and nitrogen content.
• Maintaining microbial viability through proper collection, handling, and storage according to ISO 10381-6.
• Test chemicals should be pure (>98%) with detailed molecular and physical data such as molecular weight, solubility, vapor pressure, and stability considered.

Testing Guidance

• Tests are conducted under controlled aerobic conditions that sustain microbial activity.
• Use of radiolabeled compounds can provide detailed information on degradation pathways and metabolite formation.
• Proper incubation conditions include temperature control (typically 10°C to 25°C for temperate soils), maintaining adequate oxygen and moisture levels to simulate natural conditions.
• Various methods for adding test chemicals to soils, including aqueous solutions, solvents, or as solids, minimizing toxicity and interference with microorganisms.
• Sampling frequency and number of replicates recommended to ensure statistical reliability.

Applications

SIST EN ISO 11266:2020 is critical for:

• Environmental risk assessments of pesticides, herbicides, and other agricultural chemicals.
• Testing biodegradability of industrial organic compounds released into soils.
• Supporting regulatory compliance with environmental protection agencies in Europe and worldwide.
• Guiding soil remediation efforts, helping to determine chemical persistence and degradation rates.
• Facilitating research on soil microbial processes and their effect on organic chemical transformations.
• Supporting development and validation of new test methods for biodegradation evaluation in aerobic soils.

Related Standards

This guidance document references and complements other standards related to soil quality and laboratory testing, including:

• ISO 9408:1991 – Evaluation of ultimate aerobic biodegradability of organic compounds by oxygen demand measurement.
• ISO 10381-6:1993 – Soil sampling and handling for microbial process assessments.
• ISO 10390:1994 – Soil pH determination.
• ISO 10694:1995 – Determination of organic and total carbon in soils.
• ISO 11274:1998 – Soil water retention characteristic.
• ISO 11277:2009 – Particle size distribution in soils.
• ISO 11261:1995 – Total nitrogen determination in soils.

These standards provide a robust framework for holistic evaluation of soil chemical and biological properties, crucial when interpreting biodegradation test results.

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Keywords: SIST EN ISO 11266:2020, biodegradation testing, organic chemicals, soil quality, aerobic soil conditions, laboratory guidance, environmental standards, soil microbial activity, chemical persistence, soil testing methods, environmental risk assessment.

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2020
Kakovost tal - Navodilo za laboratorijsko preskušanje biološke razgradljivosti
organskih spojin v tleh pri aerobnih pogojih (ISO 11266:1994)
Soil quality - Guidance on laboratory testing for biodegradation of organic chemicals in
soil under aerobic conditions (ISO 11266:1994)
Bodenbeschaffenheit - Anleitung für Laboratoriumsuntersuchungen zur biologischen
Abbaubarkeit von organischen Chemikalien im Boden unter aeroben Bedingungen (ISO
11266:1994)
Qualité du sol - Lignes directrices relatives aux essais en laboratoire pour la
biodégradation de produits chimiques organiques dans le sol sous conditions aérobies
(ISO 11266:1994)
Ta slovenski standard je istoveten z: EN ISO 11266:2020
ICS:
13.080.30 Biološke lastnosti tal Biological properties of soils
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 11266
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2020
EUROPÄISCHE NORM
ICS 13.080.30
English Version
Soil quality - Guidance on laboratory testing for
biodegradation of organic chemicals in soil under aerobic
conditions (ISO 11266:1994)
Qualité du sol - Lignes directrices relatives aux essais Bodenbeschaffenheit - Anleitung für
en laboratoire pour la biodégradation de produits Laboratoriumsuntersuchungen zur biologischen
chimiques organiques dans le sol sous conditions Abbaubarkeit von organischen Chemikalien im Boden
aérobies (ISO 11266:1994) unter aeroben Bedingungen (ISO 11266:1994)
This European Standard was approved by CEN on 13 April 2020.

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
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 11266:2020 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
The text of ISO 11266:1994 has been prepared by Technical Committee ISO/TC 190 "Soil quality” of the
International Organization for Standardization (ISO) and has been taken over as EN ISO 11266:2020 by
Technical Committee CEN/TC 444 “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 November 2020, and conflicting national standards
shall be withdrawn at the latest by November 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.
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 11266:1994 has been approved by CEN as EN ISO 11266:2020 without any modification.

ISO
INTERNATIONAL
STANDARD
First edition
1994-09-15
Guidance on laboratory
Soil quality -
testing for biodegradation of organic
chemicals in soil under aerobic conditions
Quakt6 du so/ - Guide relatif aux essais en laboratoire pour Ia
biodegradation de produits chimiques organiques dans Ie sol sous
conditions aerobies
Reference number
ISO 11266:1994(E)
ISO 11266:1994(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. Esch 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.
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.
International Standard ISO 11266 was prepared by Technical Committee
lSO/TC 190, Seil quality, Subcommittee SC 4, Biological methods.
Annexe A of this International Standard is for information only.
0 ISO 1994
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronie or mechanical, including photocopying and
microfilm, without Permission in writing from the publisher.
International Organization for Standardization
Case postale 56 l CH-l 211 Geneve 20 l Switzerland
Printed in Switzerland
ii
0 ISO ISO 11266:1994(E)
Introduction
Organic chemicals may be introduced into the soil both intentionally and
accidentally, after which they may, or may not, degrade biologically. For
chemicals which do degrade, the rate of degradation tan vary con-
siderably, depending not only on the molecular structure of the Chemical,
but also on soil conditions such as temperature, water and Oxygen
availability which influence microbial activity. The activity of micro-
organisms often plays a major role in degradative processes.
lt is necessary to have laboratory tests available to estimate the rate and
extent of biodegradation and thereby the persistente of organic chemicals
in soil. Numerous laboratory methods are available for the estimation of
aerobic biodegradation, but these differ considerably according to the
specific circumstances, for example, soil type, temperature and incubation
times.
This International Standard provides general guidelines for the selection
and conduct of tests for determining the biodegradation of organic
chemicals in aerobic soils.
of writing, fficient agreement
At the time there is insu on methodology for
biod egradability in anaerobic soils for guidelines to be prepared.
testing
Jhis page intentionaliy left blank

ISO 11266:1994(E)
INTERNATIONAL STANDARD o ISO
Soil quality - Guidance on laboratory testing for
biodegradation of organic chemicals in soil under aerobic
conditions
ISO 11261: -l), Soil quality - Determination of total
1 Scope
nitrogen - Kjeldahl method using titanium dioxide as
ca talys t.
This International Standard provides guidance on the
selection and conduct of appropriate test methods for
ISO 11274: -3) Soil quality - Determination of the
the determination of biodegradation of organic chemi-
wa ter re ten tion characteris tic - Labora tory me thods.
cals in aerobic soils. lt does not describe any specific
ISO 11277:- ‘1, Soil quality - Determination of
test method.
particle size dis tribu tion.
ISO 11461: -3 Soil quality - Determination o f soil
water content calculated on a volume basis -
2 Normative references
Gravime tric me thod.
The following Standards contain provisions which,
through reference in this text, constitute provisions of
3 Definitions
this International Standard. At the time of publication,
the editions indicated were valid. All Standards are
For the purposes of this International Standard, the
subject to revision, and Parties to agreements based
following definitions apply.
on this International Standard are encouraged to
investigate the possibility of applying the most recent
3.1 biodegradation: The molecular degradation of
editions of the Standards indicated below. Members
an organic substance resulting from the complex
of IEC and ISO maintain registers of currently valid
actions of living organisms.
International Standards.
3.2 primary biodegradation: The degradation of a
ISO 9408: 1991, VVater quality - Evaluation in an
substance to an extent sufficient to remove some
aqueous medium of the “ultimate ” aerobic biodegra-
characteristic property of the parent molecule. In
dability of organic compounds - Method by
practice, this will be determined by analysis as a loss
determining the Oxygen demand in a closed
of parent compound or some specific function of the
respirome ter.
parent compound.
ISO 10381-6: 1993, Soil quality - Sampling - Guid-
3.3. ultimate biodegradation: The breakdown of
ante on the collection, handling and. storage of soil for
an organic compound to carbon dioxide, water, the
the assessment of aerobic microbial processes in the
oxides or mineral salts of any other elements present,
labora tory.
and products associated with the normal metabolic
processes of microorganisms.
ISO 10390: 1994, Seil quality - Determination of pH.
3.4 persistente: The residente time of a Chemical
ISO 10694:- ‘1, Soil quality - Determination of
species in a specifically defined compartment of the
organic and total carbon after dry combustion
environment.
(“Element analysis “).
ISO 11260: 1994, Soil quality - Determination of 3.5 the disappearance time DT-50: The time taken
cation exchange capacity and base Saturation - for the concentration of a given compound to de-
Method using barrum chloride Solution. crease by 50 % of its original value.
1) To be published.
ISO 11266:1994(E) 0 ISO
2) field water content in accordance with
3.6 the disappearance time DT-90: The time taken
for the concentration of a given compound to de- ISO 11461;
crease by 90 % of its original value.
3) total water holding capacity and/or water
retention characteristic in accordance with
3.7 bound residues; non-extractable residues:
ISO 11274.
Chemical species in plants and soils, originating from,
for example, organic molecules that are not extracted
b) Chemical properties:
by methods which do not significantly Change the
Chemical nature of these residues. These non- 1) pH of the soil in accordance with ISO 10390,
extractable residues are considered to exclude or the pH in KCI Solution or CaC12 Solution;
fragments recycled through metabolic pathways
2) organic matter content in accordance with
leading to natura1 products. (For examples and further
ISO 10694;
information, see [3] in annex A.)
...