EN ISO 10634:1995
(Main)Water quality - Guidance for the preparation and treatment of poorly water-soluble organic compounds for the subsequent evaluation of their biodegradability in an aqueous medium (ISO 10634:1995)
Water quality - Guidance for the preparation and treatment of poorly water-soluble organic compounds for the subsequent evaluation of their biodegradability in an aqueous medium (ISO 10634:1995)
Restricted to the description of the four techniques for introducing the poorly-soluble organic test compounds for a subsequent test on biodegradability in an aqueous medium. The techniques are: direct addition, which is restricted to non-volatile compounds, ultrasonic dispersion of non-volatile liquid and solid compounds, adsorption on an inert support and dispersions or emulsions with an emulsifying agent. Volatile chemicals may not be tested.
Wasserbeschaffenheit - Anleitung für die Vorbereitung und Behandlung von in Wasser schwer löslichen organischen Verbindungen für die nachfolgende Bestimmung ihrer biologischen Abbaubarkeit in einem wäßrigen Medium (ISO 10634:1995)
Diese Anleitung beschreibt folgende vier Verfahren zur Dispergierung organischer Verbindungen, die auf biologische Abbaubarkeit in einem wässrigen Medium geprüft werden sollen und die nicht genügend wasserlöslich sind, um einen Test auf die übliche Weise durchzuführen: - direkte Zugabe, diese Technik ist auf nicht flüchtige Testsubstanzen begrenzt; - Dispergierung mit Ultraschall, diese Technik kann für flüssige Substanzen und solche mit einem niedrigen Schmelzpunkt verwendet werden, sofern sie nicht flüchtig sind; - Adsorption an ein inertes Trägermaterial
Qualité de l'eau - Lignes directrices pour la préparation et le traitement des composés organiques peu solubles dans l'eau en vue de l'évaluation de leur biodégradabilité en milieu aqueux (ISO 10634:1995)
La présente Norme internationale décrit quatre techniques pour la préparation des composés organiques peu solubles dans l'eau et leur introduction dans des récipients d'essai en vue d'essais de biodégradabilité en milieu aqueux selon des méthodes normalisées. Les composés à expérimenter en question ne sont pas suffisamment solubles dans l'eau pour être soumis aux essais de biodégradabilité classiques, comme décrit dans les méthodes d'essai respectives citées dans l'article 2. Les techniques de préparation sont les suivantes: -- addition directe (article 3): cette technique est réservée aux composés d'essai non volatils, si des solvants ou des supports inertes sont utilisés; -- dispersion aux ultrasons (article 4): cette technique peut être appliquée aux composés liquides non volatils et aux composés solides; -- adsorption sur un support inerte (article 5); -- dispersion ou émulsion par un émulsifiant (article 6). Les essais ultérieurs de biodégradabilité sont principalement effectués par analyse du dioxyde de carbone dégagé (voir ISO 9439) et par détermination de la consommation d'oxygène (voir ISO 9408). La présente Norme internationale ne reprend pas la description de ces méthodes; elle se limite à la description des techniques d'introduction des substances expérimentées dans le milieu d'essai et au maintien de ces substances à 383l'état dispersé. La mise en oeuvre de ces techniques doit être réalisée en respectant par ailleurs les conditions expérimentales décrites dans les méthodes normalisées pour l'évaluation de la biodégradabilité. Il convient de noter que les produits chimiques volatils ne peuvent être expérimentés suivant la méthode du dioxyde de carbone prescrite dans l'ISO 9439.
Kakovost vode - Navodilo za pripravo in obdelavo v vodi slabo topnih organskih spojin za nadaljnje vrednotenje njihove biorazgradljivosti v vodi (ISO 10634:1995)
General Information
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Standards Content (Sample)
SLOVENSKI STANDARD
01-marec-1999
Kakovost vode - Navodilo za pripravo in obdelavo v vodi slabo topnih organskih
spojin za nadaljnje vrednotenje njihove biorazgradljivosti v vodi (ISO 10634:1995)
Water quality - Guidance for the preparation and treatment of poorly water-soluble
organic compounds for the subsequent evaluation of their biodegradability in an aqueous
medium (ISO 10634:1995)
Wasserbeschaffenheit - Anleitung für die Vorbereitung und Behandlung von in Wasser
schwer löslichen organischen Verbindungen für die nachfolgende Bestimmung ihrer
biologischen Abbaubarkeit in einem wäßrigen Medium (ISO 10634:1995)
Qualité de l'eau - Lignes directrices pour la préparation et le traitement des composés
organiques peu solubles dans l'eau en vue de l'évaluation de leur biodégradabilité en
milieu aqueux (ISO 10634:1995)
Ta slovenski standard je istoveten z: EN ISO 10634:1995
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.
0 ISO
ISO 10634:1995(E)
Introduction
The standardizing work carried out by lSO/TC ‘l47/SC 5 has shown that
the development of a Single method for evaluating the biodegradability of
organic compounds with a low solubility in water may not be envisaged
in the immediate future. In fact, the selection of the most suitable working
method to obtain a satisfactory emulsion or dispersion of these com-
pounds in the test media depends particularly on their physico-Chemical
properties. Consequently, the selection of the most suitable method has
to be left to the judgement of laboratories responsible for the tests based
on their experience and the product information supplied by the applicant.
lt is for this reason that this International Standard describes various
techniques for treating poorly soluble organic compounds before they are
investigated in biodegradability tests, with the aim of reaching a Stage
where, for any given technique, the same working method is used by all
laboratories, thus making it easier to compare results.
The techniques described in this International Standard do not necessarily
produce the Same results if they are used in parallel. The use of solvents
and dispersing or emulsifying techniques may be additional sources of
errors and may lead to test results which differ from those obtained
without using these techniques. Furthermore, dispersions or emulsions
may be produced which would not exist as such in nature and where the
rate and degree of biodegradability is enhanced because very fine particles
are present. These facts have to be considered for the evaluation and in-
terpretation of the results of biodegradation tests. lt is recommended to
perform biodegradability tests first, with the direct addition of a test com-
pound, or to perform this test in parallel to tests using dispersion tech-
niques.
Normally, only pure or virtually pure compounds should be tested. If mix-
tures or multi-componental substances are tested, the use of solvents and
dispersion techniques may lead to unrepresentative heterogeneous dis-
tributions and to misleading test results in the subsequent biodegradability
tests.
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INTERNATIONAL STANDARD 0 ISO ISO 10634:1995(E)
Water quality - Guidance for the preparation and
treatment of poorly water-soluble organic compounds
for the subsequent evaluation of their biodegradability
in an aqueous medium
volatile chemicals may not be tested by the carbon
1 Scope
dioxide method specified in ISO 9439.
This International Standard describes four techniques
2 Normative references
for preparing poorly water-soluble organic compounds
and introducing them into test vessels for a sub-
The following Standards contain provisions which,
sequent test on biodegradability in an aqueous me-
through reference in this text, constitute provisions
dium using Standard methods. The test compounds
of this International Standard. At the time of publica-
concerned are not sufficiently soluble in water to
tion, the editions indicated were valid. All Standards
perform the biodegradability tests in the normal man-
are subject to revision, and Parties to agreements
ner, as described in the respective test methods indi-
based on this International Standard are encouraged
cated in clause 2.
to investigate the possibility of applying the most re-
cent editions of the Standards indicated below.
The preparation techniques are as follows:
Members of IEC and ISO maintain registers of cur-
- direct addition (clause 3): this technique is re- rently valid International Standards.
stricted to non-volatile test compounds if inert
ISO 9408: 1991, Water quality - Evaluation in an
supports or solvents are used;
aqueous medium of the “ultimate ” aerobic bio-
degradability of organic compounds - Method by
- ultrasonic dispersion (clause 4): this technique
determining
may be applied to non-volatile liquid and solid the Oxygen demand in a closed
compounds; respirome ter.
- adsorption on an inert support (clause 5); ISO 9439: 1990, Water quality - Evaluation in an
aqueous medium of the “ultimate ” aerobic bio-
- dispersions or emulsions with an emulsifying
degradability of organic compounds - Method by
agent (clause 6). analysis of released carbon dioxide.
The subsequent tests on biodegradability are primarily
3 Direct addition
methods using the analysis of the released carbon
dioxide (see ISO 9439) and the determination of the
Any of the following techniques tan be used
Oxygen consumption (see ISO 9408). This Inter-
national Standard does not describe the test methods;
- The test compound is weighed and directly intro-
it is restricted to describing the techniques for intro-
duced into the test vessels which are subjected to
ducing the test substances into the test medium and
continuous agitation.
to keep them in a dispersed state. These techniques
are implemented while observing the experimental
NOTE 1 Some organic compounds which are spar-
conditions described in the standardized methods for
ingly soluble in water dissolve more readily when alkali
or acid is added. They may be introduced as an acid or
evaluating biodegradability. lt should be noted that
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ISO 10634:1995(E)
alkaline stock Solution, provided that no substantial re-
Test compounds which are sufficiently soluble in wa-
action of the test compound takes place. The test me-
ter under acidic or alkaline conditions may be intro-
dium is adjusted to neutral before the inoculum is
duced as stock Solution. Prepare a stock Solution of
added.
such a test compound in deionized water adjusted
with inorganic acid or alkali to a sufficiently high or low
- The test compound is weighed onto a suitable
pH. Add an appropriate amount of the stock Solution
inert support and introduced into the test vessels
to the test medium to obtain the desired concen-
which are subjected to continuous agitation.
tration of the test compound in the test vessels.
Measure the pH of the medium and adjust it as
- A Solution of the test compound is prepared in a
necessary before the inoculum is added.
volatile organic solvent and is introduced into the
test vessels which are subjected to continuous
3.3.2 Using a support
agitation.
The solvent, which shall be used in minimal Grind solid test compounds as finely as possible be-
amounts, is then removed, if possible completely, fore weighing them. Weigh the liquids, including
viscous substances, without treatment or, if possible,
by agitation before the test medium is added.
solidify in liquid nitrogen and grind finely before
weighing.
3.1 Reagents
Weigh onto the support (32.1) a quantity of the
A volatile organic solvent is selected for its capacity
compound corresponding to the initial concentation
to dissolve the test compound.
or organic carbon required by the test method to be
used.
The Chosen solvent shall not react with the test
compound or with any component of the medium.
Introduce a support into each of the test vessels, and
also introduce a support without the tes t compound
The solvent shall be non-biodegradable and non-toxic
into each of the control vessels.
to bacteria under the conditions of the subsequent
biodegradability tests, especially if it cannot be re-
Maintain agitation using the stirrers (3.22 ) throughout
moved sufficiently.
the biodegradability test.
Suitable solvents are acetone or dichloromethane.
3.3.3 Using a solvent
3.2 Apparatus
Prepare a Solution of the test compound in a mini-
mum of the Chosen organic solvent (3.1).
32.1 Inert supports, which may be introduced into
Introduce, into the test vessels, the quantity of sol-
the test vessels, e.g. microscope slides.
ution needed to obtain the initial concentration of or-
ganic carbon required by the test method used.
3.22 Stirrers, in sufficient numbers to ensure that
all the test vessels used in the respective biodegrad-
Introduce the Same quantity of the solvent, without
ability tests tan be agitated.
any test compound, into each of the control vessels.
Stirrer-rods shall be of such a material that no in-
Evaporate the solvent, if possible completely, by ap-
gredients of a plastics coat will contaminate the test
propriate methods.
medium and no adsorption of test compounds will
occur. Heating up the test vessels by stirring and
NOTE 2 The test Solution may be spread over the base
raising the test temperature shall be avoided. of the test vessels and the System is then purged with gas
and/or stirred. The last traces of solvent are difficult to re-
move. Interferences may occur if the solvent is biodegrad-
3.3 Procedure
able or inhibitory to bacteria.
Then carry out the biodegradability test.
3.3.1 Direct addition
Test compounds with crystalline structures may be
4 Ultrasonic dispersion
weighed and directly added to the test vessels.
compounds may be added with a An emulsion or dispersion of the compound to be
Non-visco us liquid
e. tested is prepared using an ultrasonic probe and is
high preci sion volu metric syring
0 ISO
ISO 10634:1995(E)
introduced into the test vessels, which are continu- centration of organic carbon required by the test
ously agitated (see 3.22). method to be used.
Sustain the agitation throughout the biodegradability
test.
4.1 Apparatus
NOTE 5 It may be difficult to obtain a stable emuision or
dispersion. Special care is therefore required when aliquots
Ultrasonic transducer, capable of producing
4.1.1
are distributed to the test vessels. if it proves impossible to
a frequency of approximately 20 kHz.
obtain a sufficiently stable emulsion or a sufficiently high
concentration to carry out the test, the test compound may
be introduced directly into the test medium and be dis-
4.12 Stirrers, in sufficient numbers to ensure that
persed ultrasonically in the test vessels before the inoculum
all the test vessels tan be agitated (see 32.2).
is added.
4.2 Procedure
5 Adsorption on an inert support
Add, for example, 10 g or IO ml of the test compound
The test compound is adsorbed onto an inert support
to a 500 ml beaker containing approximately 400 ml
and introduced into the test vessels. lt is kept dis-
of deionized water.
persed in the medium by continuous agitation.
The test compound shall be present in excess so that
a saturated Solution is obtained. Install the ultrasonic
transducer (4.1 .l) in such a way that its tip is as close 5.1 Reagents
as possible to the interface between the water and
the test compound.
5.1.1 Inert support
(4.1.2) to agitate the beaker so that the
Use a stirrer
Silica gel, glassfibre filters or other non-biodegradable
compound is drawn down to the bottom.
inert suppot-ts which do not release organic or inor-
ganic carbon into the aqueous medium may be used.
Set the transducer to give a frequency of about
20 kHz and maintain this for about 30 min.
lt should be validated by preliminary work that the
support is inert and carbon-free; to avoid or minimize
Switch off the transducer and leave the emulsion or
surface area effects, the quantity of the support shall
dispersion to settle Tor 15 min to 30 min, then decant
be minimal. The test compound should be adsorbed
it off from the excess test compound into another
on the surface but not be adsorbed and fixed too in-
Container.
tensively on the support.
NOTES
NOTE 6 For example, if silica gel is used, the following
and figures are given only as a guide.
3 The proportions supports are suitable:
characteristics of the test comp lound.
They depend on the
- silica g el used for thin-layer chro matog raphy (15 Fm
4 Some substances are subjected to thermal decompo-
particle size);
sition if heat generation occurs at the probe tip. This may
also lead to an increase in the temperature of the bulk sol-
- silica gel used for col umn chromatography (200 Pm to
ution. This Problem may be avoided by measuring and
500 Pm p article size).
controlling the temperature, reduction of the power of the
sonifier or intermittent sonification. In some cases, prob-
lems may be encountered because of the destruction of the 5.1.2 Solvent
Chemical. If this is the case, a different method should be
used. A volatile solvent is selected for its capacity to dis-
solve the test compound.
Using an appropriate analytical method [specific
analysis or total organic carbon (TOC) analysis], ana- lt shall be non-toxic to bacteria and, if possible, non-
lyse an aliquot of the emulsion or dispersion obtained biodegradable under the conditions of the subsequent
and determine the concentration of the test com- biodegradability tests. This shall be tested in advance
or in the subsequent biodegradability test.
pound.
Introduce an appropriate volume of emuls Iion or dis- Depending on the test compound, acetone or
persion into the test vessels to o btain the initial con- dichloromethane may be suitable
...
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