SIST EN ISO 10707:1998

Water quality - Evaluation in an aqueous medium of the "ultimate" aerobic biodegradability of organic compounds - Method by analysis of biochemical oxygen demand (closed bottle test) (ISO 10707:1994)

Specifies a method, by analysis of biochemical oxygen demand, for the evaluation in an aqueous medium of the "ultimate" biodegradability of organic compounds at a given concentration by aerobic microorganisms. The method applies to all organic compounds which are sufficiently water soluble to prepare a stock solution or poorly water soluble when using special dosing techniques.

Wasserbeschaffenheit - Bestimmung der vollständigen aeroben biologischen Abbaubarkeit organischer Stoffe in einem wäßrigen Medium - Verfahren mittels Bestimmung des biochemischen Sauerstoffbedarfs (Geschlossener Flaschentest) (ISO 10707:1994)

Diese Internationale Norm beschreibt ein Verfahren zur Bestimmung der vollständigen biologischen Abbaubarkeit einer organischen Substanz bei einer vorgegebenen Konzentration in einem wäßrigen Medium durch aerobe Mikroorganismen. Die in dieser Internationalen Norm beschriebenen Bedingungen entsprechen nicht immer den optimalen Bedingungen, um einen maximalen biologischen Abbaugrad zu erreichen.

Qualité de l'eau - Evaluation en milieu aqueux de la biodégradabilité aérobie ultime des composés organiques - Méthode par anylyse de la demande biochimique en oxygene (essai en fiole fermées) (ISO 10707:1994)

La présente Norme internationale prescrit une méthode, par analyse de la demande biochimique en oxygène, d'évaluation de la biodégradabilité «ultime» de composés organiques présents à une concentration donnée sous l'action de micro-organismes aérobies. Les conditions décrites dans la présente Norme internationale ne correspondent pas nécessairement aux conditions optimales d'obtention de la biodégradation maximale. La méthode s'applique à tout composé organique suffisamment soluble dans l'eau pour préparer une solution mère ou peu soluble dans l'eau à l'aide de techniques de dosage particulières. En général, en raison de la faible concentration en composé à expérimenter au début de l'essai, il n'est pas nécessaire de prendre des précautions spéciales relatives à la toxicité du composé à expérimenter vis-à-vis des micro-organismes de l'inoculum. Si nécessaire, un essai d'inhibition peut être effectué en parallèle.

Kakovost vode - Vrednotenje “končne” aerobne razgradljivosti organskih snovi v vodi - Določanje biokemijske potrebe po kisiku (preskus v zaprtih steklenicah) (ISO 10707:1994)

General Information

• Status: Published
• Publication Date: 30-Apr-1998
• ICS: 13.060.70 - Examination of biological properties of water
• Technical Committee: KAV - Water quality
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-May-1998
• Due Date: 01-May-1998
• Completion Date: 01-May-1998
• Ref Project: EN ISO 10707:1997 - Water quality - Evaluation in an aqueous medium of the "ultimate" aerobic biodegradability of organic compounds - Method by analysis of biochemical oxygen demand (closed bottle test) (ISO 10707:1994)

Relations

• Replaces: SIST ISO 10707:1997 - Water quality -- Evaluation in an aqueous medium of the "ultimate" aerobic biodegradability of organic compounds -- Method by analysis of biochemical oxygen demand (closed bottle test)
• Effective Date: 01-May-1998

Overview

SIST EN ISO 10707:1998 is an international standard developed by the European Committee for Standardization (CEN) in alignment with ISO 10707:1994. It specifies a standardized method for evaluating the ultimate aerobic biodegradability of organic compounds in aqueous media. The method assesses the biodegradability by measuring the biochemical oxygen demand (BOD) using the closed bottle test. This procedure determines the extent to which microorganisms degrade an organic compound by monitoring oxygen consumption under aerobic conditions over a set incubation period.

The standard applies broadly to organic compounds that are sufficiently soluble in water, including those poorly soluble compounds when special dosing techniques are applied. This method is essential for water quality assessment, environmental monitoring, and regulatory compliance.

Key Topics

• Ultimate Aerobic Biodegradability: Defined as the complete microbial degradation of an organic compound into carbon dioxide, water, mineral salts, and microbial biomass under aerobic conditions.

• Biochemical Oxygen Demand (BOD): The primary measurement used to evaluate the amount of oxygen consumed by microorganisms as they biodegrade organic compounds over 28 days.

• Test Medium Composition: The method utilizes a mineral medium with specific nutrients and buffers to sustain microbial activity without interference.

• Inoculum Preparation: Inoculum is typically sourced from activated sludge or secondary effluent, representing mixed microbial populations capable of degrading the test compound.

• Test Procedure:

  • Preparation of the test compound solution in the mineral medium.
  • Incubation in sealed, water-filled bottles in the dark at 20-25°C.
  • Measurement of dissolved oxygen concentration at zero time, and periodically up to 28 days.
  • Parallel tests with reference compounds and blanks to validate results and check for toxicity or inhibition effects.

• Data Interpretation and Calculation:
  Biodegradability is expressed as the percentage of theoretical oxygen demand (ThOD) or chemical oxygen demand (COD) consumed. Corrections for oxygen uptake due to nitrification are applied when nitrogen-containing compounds are tested.

• Safety Precautions: Caution is emphasized when handling sewage sludge or activated sludge, as they may contain pathogenic microorganisms. Test compounds with unknown toxicity should be handled carefully.

Applications

SIST EN ISO 10707:1998 is widely used in:

• Environmental Assessment: Rapid evaluation of the biodegradability potential of chemicals to predict environmental fate.

• Water Quality Monitoring: Assessing organic pollutants in wastewater and natural waters to understand their impact on oxygen levels and aquatic life.

• Regulatory Compliance: Providing standardized test methods required by environmental agencies to categorize chemicals as biodegradable or persistent.

• Wastewater Treatment Optimization: Determining the biodegradability of industrial effluents and chemicals to optimize biological treatment processes.

• Research and Development: Supporting the design of environmentally friendly chemicals by assessing their ultimate biodegradability early in product development.

Related Standards

This standard complements and references several other water quality and biodegradability standards:

• ISO 5813 / ISO 5814: Methods for dissolved oxygen determination-iodometric and electrochemical probe methods.

• ISO 9887:1992: Semi-continuous activated sludge method for aerobic biodegradability evaluation.

• ISO 9888:1991: Static test (Zahn-Wellens method) for aerobic biodegradability.

• ISO 10304-2: Ionic analysis in wastewater for nitrite and nitrate measurements required for nitrification correction.

• ISO 10634: Guidance on evaluation of ultimate biodegradation in aqueous medium for poorly soluble compounds.

• ISO 6060: Chemical oxygen demand (COD) test.

This suite of standards provides comprehensive methodologies for evaluating biodegradability and water quality parameters, ensuring reliable, reproducible, and comparable results globally.

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Keywords: EN ISO 10707, ultimate aerobic biodegradability, biochemical oxygen demand, BOD test, closed bottle test, organic compounds, water quality, environmental monitoring, biodegradation testing, aquatic toxicity, chemical oxygen demand, aerobic microorganisms, wastewater treatment, ISO standards.

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-1998
1DGRPHãþD
SIST ISO 10707:1997
.DNRYRVWYRGH9UHGQRWHQMH³NRQþQH´DHUREQHUD]JUDGOMLYRVWLRUJDQVNLKVQRYLY
YRGL'RORþDQMHELRNHPLMVNHSRWUHEHSRNLVLNXSUHVNXVY]DSUWLKVWHNOHQLFDK
,62
Water quality - Evaluation in an aqueous medium of the "ultimate" aerobic
biodegradability of organic compounds - Method by analysis of biochemical oxygen
demand (closed bottle test) (ISO 10707:1994)
Wasserbeschaffenheit - Bestimmung der vollständigen aeroben biologischen
Abbaubarkeit organischer Stoffe in einem wäßrigen Medium - Verfahren mittels
Bestimmung des biochemischen Sauerstoffbedarfs (Geschlossener Flaschentest) (ISO
10707:1994)
Qualité de l'eau - Evaluation en milieu aqueux de la biodégradabilité aérobie ultime des
composés organiques - Méthode par anylyse de la demande biochimique en oxygene
(essai en fiole fermées) (ISO 10707:1994)
Ta slovenski standard je istoveten z: EN ISO 10707:1997
ICS:
13.060.70 Preiskava bioloških lastnosti Examination of biological
vode properties of water
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

INTERNATIONAL
ISO
STANDARD
First edition
1994-10-15
Water quality - Evaluation in an aqueous
medium of the “ultimate” aerobic
biodegradability of organic compounds -
Method by analysis of biochemical Oxygen
demand (closed bottle test)
Quake de I’eau - i%aluation en milieu aqueux de Ia biodegradabilitk
akobie wltime)) des composes organiques - Methode par analyse de
Ia demande biochimique en oxygkne (essai en fiole fermee)
Reference number
ISO 10707:1994(E)
EO ?0707:1994(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
(1 EC) 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 10707 was prepared by Technical Committee
lSO/TC 147, Water quality, Subcommittee SC 5, Biological methods.
Annexes A, B and C of this International Standard are 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 mechanicai, Inciudrng phorocopying and
mtcrofilm, without permrssion In writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-l 211 Geneve 20 l Switzerland
Printed rn Switzerland
ii
INTERNATIONAL STANDARD 0 ISO
ISO 10707:1994(E)
Water quality - Evaluation in an aqueous medium of
the “ultimate” aerobic biodegradability of organic
compounds - Method by analysis of biochemical
Oxygen demand (closed bottle test)
WARNING - SAFETY PRECAUTIONS - Activated sludge and sewage may contain potentially
pathogenic organisms. Therefore appropriate precautions should be taken when handling them.
Toxic test compounds and those whose properties are unknown should be handled with care.
are subject to revision, and Parties to agreements
1 Scope
based on this International Standard are encouraged
to investigate the possibility of applying the most re-
This International Standard specifies a method, by
cent editions of the Standards indicated below.
analysis of biochemical Oxygen demand, for the
Members of IEC and ISO maintain registers of cur-
evaluation in an aqueous medium of the “ultimate”
rently valid International Standards.
biodegradability of organic compounds at a given
concentration by aerobic microorganisms.
ISO 58137 983, Water quality - Determination of
dissolved Oxygen - lodome tric me thod.
The conditions described in this International Standard
do not necessarily always correspond to the optimal
ISO 5814:1990, Water quality - Determination of
conditions for allowing the maximum value of bio-
dissolved Oxygen
- Electrochemical probe method.
degradation to occur.
ISO 60603 989, Water quality - Determination of the
The method applies to all organic compounds which
are sufficiently water soluble to prepare a stock sol- Chemical Oxygen demand.
ution or poorly water soluble when using special dos-
ISO 9887:1992, Water quality - Evaluation of the
ing techniques.
aerobic biodegradability of organic compounds in an
Due to the low concentration of test compound at the
aqueous medium - Semi-continuous activated
beginning of the test, normally no special precautions
sludge method (SCAS).
for the toxicity of the test compound to the micro-
oroanisms of the inoculum is necessary; if required a ISO 9888: 1991, Wa ter quality - Evaluation of the
parallel inhibition test tan be performed. aerobic biodegradability of organic compounds in an
aqueous medium
- Static test (Zahn-WeIlens
me thod).
2 Normative references
ISO 10304-2: --J), Water quality - Determination of
dissolved anions by liquid chromatography of ions -
The following Standards contain provisions which,
Part 2: Determination o f bromide, chloride, nitra te,
through reference in this text, constitute provisions
nitrite, orthophosphate and sulfite in vvaste vvater.
sf this International Standard. At the time of publi-
cation, the editions indicated were valid. All Standards
1) To be published.
63 ISO
ISO 10707:1994(E)
ISO 10634:-IJ, Water quality - Guidance for the of dissolved Oxygen over a period of 28 d. The
amount of Oxygen taken up by the test Chemical
evaluation in an aqueous medium of the “ultjmate ”
soluble organic (BOD), corrected for uptake by the blank inoculum run
biodegradability of poorly
compounds. in parallel, is expressed as percentage of ThOD or
COD.
3 Definitions
5 Test environment
For the purposes of this International Standard, the
Incubation shall take place in the dark in an enclosure
following definitions apply.
which is maintained at a constant temperature (within
+ 1 “C) between 20 “C and 25 “C.
-
3.1 ultimate biodegradation: The level of degra-
dation achieved when the test compound is totally
utilized by microorganisms resulting in the production
6 Reagents
of carbon dioxide, water, mineral salts and new
microbial cellular constituents (biomass). Use only reagents of recognized analytical grade.
3.2 biochemical Oxygen demand (BOD): The mass
6.1 Water
concentration of dissolved Oxygen consumed under
specified conditions by the biological Oxidation of or-
Distilled or deionized water free from inhibitory con-
ganic and/or inorganic matter in water and is ex-
centrations of toxic substances containing less than
pressed in this case as milligrams of Oxygen uptake
10 % of the initial DOC content introduced by the
per milligram or gram of test compound.
compounds to be tested. For each series of tests, use
only one batch of water.
3.3 Chemical Oxygen demand (COD): The amount
of Oxygen consumed during Oxidation of a test com-
6.2 Test medium
pound with hot, acidic dichromate. lt provides a
measure of the amount of oxidizable matter present
and is expressed in this case as milligrams of Oxygen 6.2.1 Composition
consumed per milligram or gram of test compound.
6.2.1 . ‘l Solution a)
3.4 theoretical Oxygen demand (ThOD): The total
amount of Oxygen required to oxidize a Chemical
Anhydrous potassium dihydrogenphosphate
completely. lt is calculated from the molecular formula
KH,PO,) 65 g
and is expressed in this case as milligrams of Oxygen
Anhydrous dipotassium hydrogenphosphate
required per milligram or gram of test compound.
Zl,75 g
K2HP0,)
Disodium hydrogenphosphate dihydrate
3.5 pre-exposure (or pre-adaptation): The pre-
33,4 g
(Na,HPO,.ZH,O)
incubation of an inoculum in the presence of the test
Ammonium chloride (NH,CI)
Q5 g
compound, with the aim of enhancing the ability of
the inoculum to degrade the test compound. If the
Dissolve the ingredients in water (6.1) and make up
aim is achieved, the inoculum is said to be adapted.
to 1 000 ml.
3.6 pre-conditioning (or pre-acclimatization): The
NOTE ‘1 The correct composition of the medium tan be
pre-incubation of an inoculum under the conditions of
checked by the measurement of the pH-value, which should
the test in the absence of the test compound, to im- be 7.4.
prove the Performance of the test.
6.2.1.2 Solution b)
Dissolve 22,5 g of magnesium sulfate heptahydrate
4 Principle
(MgS0,.7H,O) in water (6.1) and dilute to 1 000 ml.
A Solution of the organic test compound in a mineral
medium as the sole Source of carbon and energy is
6.2A.3 Solution c)
inoculated with a relatively small number of micro-
Drssolve 27,5 g of anhydrous Calcium chlonde (CaCl,
organisms from a mixed population and kept in com-
pletely full, closed bottles in the dark at a constant or 36,4 g of calcrum chloride dihydrate iCaCl,.2H,O
temperature. Biodegradation is followed by analysis in water (6.11 and dilute to 1 000 ml.
0 ISO ISO 10707:1994(E)
bottles (7.3) containing a known volume of test me-
6.2.1.4 Solution d)
dium (6.2.2) so that the final concentration of the
Dissolve 0,25 g of iron(lll) chloride hexahydrate Chemical is normally 2 mg/l. This concentration is in
(FeCI,.GH,O) in water (6.1) and dilute to 1 000 ml. general suitable to ensure that the concentration of
Oxygen does not fall below 0,5 mg/1 during the test
In Order to avoid having to prepare this Solution im-
and the inoculum activity is not limited. For poorly
mediately before use, add one drop of concentrated
biodegradable compounds and those with a low
hydrochloric acid (HCI) or 0,4 g of ethylenediamine-
ThOD, up to IO mg/1 may be used.
tetraacetic acid (EDTA) (disodium salt) per Iitre.
In some cases, for example if a poor or partial degra-
dation is expected, it would be advisable to run paral-
6.2.2 Preparation of the test medium
lel series of test Chemical at two different
For 1 litre of test medium, add 1 ml of each of the
concentrations, for example 2 mg/1 and 5 mg/l.
solutions a) to d) (6.2.1) to about 500 ml of water
Normally, calculate the ThOD on the basis of forma-
(6.1) and adjust the volume to 1 000 ml.
tion of ammonium salts but, if nitrification is expected
or known to occur, calculate the ThOD on the basis
Strongly aerate the test medium for at least 20 min.
of the formation of nitrate. However, if nitrification is
Carry out each series of tests with test medium de-
not complete but does occur, correct for the changes
rived from the same batch. Generally, the medium is
in concentration of nitrite and nitrate, determined by
ready for use after standing for 20 h at the test tem-
analysis (see annex C).
perature. Determine the concentration of dissolved
Oxygen for control purposes; the value should be
In the case of test compounds that are very poorly
about 9 mg/1 at 20 “C. Conduct all transfer and filling
soluble in water for which no stock Solution tan be
operations of the air-saturated medium bubble-free, prepared, add the test compound in the required
for example, by the use of Siphons. quantity directly to the BOD bottles (7.1). Use the
large bottles (7.3) only to add inoculated test medium
(6.2.2). Avoid loss of test medium and test compound
7 Apparatus
when stoppering the bottles. For alternatives or more
details see ISO 10634.
Usual laboratory equipment, and
8.2 Preparation of reference compound
with glass Stoppers, of c apacity
7.1 BOD bottles
The bottles tan be made airtight Solution
250 ml to 300 ml.
case, only grease which is free of
by greasing. In this
Prepare a stock Solution of a known biodegradable
hall be
organic carbon, for . example Silicon grease, s
organic substance, for example sodium acetate,
used.
sodium benzoate or aniline, in the test medium
(6.2.2). In the same way as with the test compound,
7.2 Water bath or incubator, for keeping bottles
add a sufficient amount of the stock Solution to the
at a constant test temperature with the exclusion of
.
large bottles (7.3) to give a test concentration of
Irght .
2 mg/l.
7.3 Large glass bottles, of capacity 2 litres to
8.3 Preparation of inhibition control
5 litres, for the preparation of media and for filling the
BOD bottles.
If the toxicity of the test compound is to be investi-
gated (for example in the case of a previous low bio-
meter, or equ ipmen t for
7.4 Oxygen electrode and
degradability value having been found), another series
iodo metric Oxygen determina tion.
of bottles is necessary. Prepare another large bottle
(7.3) containing aerated mineral medium plus test
7.5 pH-meter.
compound and reference compound at final concen-
trations that are the same as those in the other large
bottles. Add the mixture to the BOD bottles (7.1).
8 Procedure
8.4 Preparation of the inoculum
8.1 Preparation of test compound solution
In this test use an inoculum without sludge flocs. lt
Prepare a stock Solution of the test compound in wa-
should be derived from the secondary effluent 0% a
ter (6.1) or test medium (6.2.2) (e.g. i g/l). Add a suf-
treatment plant or laboratory-scale unit receiving pre-
ficient amount of the stock Solution to the large
ISO %0707: ‘P994(E)
- at least IO bottles containing reference compound
dominantly domestic sewage or from surface watet-.
Mixtures from these different sources may also be and inoculum (FC);
used.
- at least IO bottles containing only inoculum (blank)
.
Collect a fresh Sample and keep it aerobic during
(FM I
transport. If suspended solids are present, allow to
settle for 1 h or filter through a coarse filter Paper and
and if necessary
keep the Sample under aerobic conditions until it is
required. - at least 6 bottles conta
...