SIST EN ISO 18856:2005

SLOVENSKI STANDARD
SIST EN ISO 18856:2005
01-december-2005
.DNRYRVWYRGH±'RORþHYDQMHL]EUDQLKIWDODWRYVSOLQVNRNURPDWRJUDILMRPDVQR
VSHNWURPHWULMR,62
Water quality - Determination of selected phthalates using gas chromatography/mass
spectrometry (ISO 18856:2004)
Wasserbeschaffenheit - Bestimmung ausgewählter Phthalate mittels
Gaschromatographie/Massenspektrometrie (ISO 18856:2004)
Qualité de l'eau - Dosage de certains phtalates par chromatographie en phase
gazeuse/spectrométrie de masse (ISO 18856:2004)
Ta slovenski standard je istoveten z: EN ISO 18856:2005
ICS:
13.060.50 3UHLVNDYDYRGHQDNHPLþQH Examination of water for
VQRYL chemical substances
SIST EN ISO 18856:2005 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 18856:2005

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SIST EN ISO 18856:2005
EUROPEAN STANDARD
EN ISO 18856
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2005
ICS 13.060.50

English Version
Water quality - Determination of selected phthalates using gas
chromatography/mass spectrometry (ISO 18856:2004)
Qualité de l'eau - Dosage de certains phtalates par Wasserbeschaffenheit - Bestimmung ausgewählter
chromatographie en phase gazeuse/spectrométrie de Phthalate mittels
masse (ISO 18856:2004) Gaschromatographie/Massenspektrometrie (ISO
18856:2004)
This European Standard was approved by CEN on 20 July 2005.
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 Central Secretariat 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2005 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 18856:2005: E
worldwide for CEN national Members.

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SIST EN ISO 18856:2005
EN ISO 18856:2005 (E)
Foreword
The text of ISO 18856:2004 has been prepared by Technical Committee ISO/TC 147 "Water quality" of the
International Organization for Standardization (ISO) and has been taken over as EN ISO 18856:2005 by
Technical Committee CEN/TC 230 “Water analysis”, the secretariat of which is held by DIN.
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 February 2006, and conflicting national standards shall be withdrawn
at the latest by February 2006.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland
and United Kingdom.

Endorsement notice
The text of ISO 18856:2004 has been approved by CEN as EN ISO 18856:2005 without any modifications.
2

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SIST EN ISO 18856:2005


INTERNATIONAL ISO
STANDARD 18856
First edition
2004-09-15

Water quality — Determination of
selected phthalates using gas
chromatography/mass spectrometry
Qualité de l'eau — Dosage de certains phtalates par chromatographie
en phase gazeuse/spectrométrie de masse




Reference number
ISO 18856:2004(E)
©
ISO 2004

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SIST EN ISO 18856:2005
ISO 18856:2004(E)
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©  ISO 2004
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
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ii © ISO 2004 – All rights reserved

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SIST EN ISO 18856:2005
ISO 18856:2004(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope. 1
2 Normative references . 2
3 Principle . 2
4 Interferences. 3
5 Reagents . 3
6 Apparatus. 5
7 Sampling and sample pre-treatment. 7
8 Procedure. 7
9 Calibration. 10
10 Calculation. 13
11 Expression of results. 15
12 Precision . 15
13 Test report. 15
Annex A (informative) List of phthalates. 16
Annex B (informative) General remarks. 18
Annex C (normative) Precision data. 19
Annex D (informative) Examples of solutions (overview) . 22
Annex E (informative) Example of equipment to avoid contaminations. 25
Annex F (informative) Examples of suitable capillary columns . 29
Annex G (informative) Example of gas chromatographic conditions. 30
Bibliography . 32

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SIST EN ISO 18856:2005
ISO 18856:2004(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 18856 was prepared by Technical Committee ISO/TC 147, Water quality, Subcommittee SC 2, Physical,
chemical and biochemical methods.
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SIST EN ISO 18856:2005
ISO 18856:2004(E)
Introduction
The user should be aware that particular problems could require the specification of additional marginal
conditions.

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SIST EN ISO 18856:2005

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SIST EN ISO 18856:2005
INTERNATIONAL STANDARD ISO 18856:2004(E)

Water quality — Determination of selected phthalates using gas
chromatography/mass spectrometry
WARNING — Persons using this International Standard should be familiar with normal laboratory
practice. This International Standard does not purport to address all of the safety problems, if any,
associated with its use. It is the responsibility of the user to establish appropriate safety and health
practices and to ensure compliance with any national regulatory conditions.
IMPORTANT — It is absolutely essential that tests conducted according to this International Standard
be carried out by suitably trained staff.
1 Scope
This International Standard specifies a method for the determination of phthalates in water after solid phase
extraction and gas chromatography/mass spectrometry.
This method is applicable to the determination of phthalates (see Table 1) in ground water, surface water,
wastewater and drinking water in mass concentrations ranging from above 0,02 µg/l up to 0,150 µg/l,
depending on the individual substance and the value of the blank.
The applicability of this method to other phthalates not specified in Table 1 is not excluded, but it is necessary
to determine its applicability in each case (see Annex A for the list of phthalates).
General remarks concerning the recovery and use of internal standards is given in Annex B.
Table 1 — Phthalates determined by this method
Molar mass
a
No Name Formula Abbreviation CAS number
g/mol
1 Dimethyl phthalate C H O DMP 194,2 131-11-3
10 10 4
2 Diethyl phthalate C H O DEP 222,24 84-66-2
12 14 4
3 Dipropyl phthalate C H O DPP 250,3 131-16-8
14 18 4
4 Diisobutyl phthalate C H O DiBP 278,4 84-69-5
16 22 4
5 Dibutyl phthalate C H O DBP 278,4 84-74-2
16 22 4
6 Butyl benzyl phthalate C H O BBzP 312,4 85-68-7
19 20 4
7 Dicyclohexyl phthalate C H O DCHP 330,4 84-61-7
20 26 4
8 Di(2-ethylhexyl) phthalate C H O DEHP 390,6 117-81-7
24 38 4
9 Di(n-octyl) phthalate C H O DOP 390,6 117-84-0
24 38 4
10 Didecyl phthalate C H O DDcP 446,7 84-77-5
28 46 4
11 Diundecyl phthalate C H O DUP 474,4 3648-20-2
30 50 4
a
CAS: Chemical Abstracts System.
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SIST EN ISO 18856:2005
ISO 18856:2004(E)
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 reference document
(including any amendments) applies.
ISO 5667-1, Water quality — Sampling — Part 1: Guidance on the design of sampling programmes
ISO 5667-2, Water quality — Sampling — Part 2: Guidance on sampling techniques
ISO 5667-3, Water quality — Sampling — Part 3: Guidance on the preservation and handling of water samples
3 Principle
Extraction of the compounds from the water by solid-phase extraction. Then separation is accomplished using
capillary columns by gas chromatography and followed by identification and quantification of the phthalates by
mass spectrometry. The principle of this method is outlined in Figure 1.

Figure 1 — Flowchart of the analysis
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SIST EN ISO 18856:2005
ISO 18856:2004(E)
4 Interferences
IMPORTANT — Due to their use as plasticizer agents, phthalates are ubiquitous. Therefore, pay
special attention to avoid any contamination.
4.1 Interferences during sampling
In order to avoid interferences and cross-contamination, do not use plastics materials (pipes, etc.).
4.2 Interferences during enrichment
Commercially available adsorbent materials are often of varying quality. Considerable batch-to-batch
differences in quality and selectivity of this material are possible. The recovery of single substances may vary
with concentration. Therefore, check the recovery regularly at different concentration levels and whenever
new batches are used. Perform calibration and analysis with material from the same batch.
Cross-contamination is likely to occur with laboratory air. Therefore, remove, as far as possible, plastics
materials from the laboratory. Cleaning agents often contain phthalates and may severely contaminate the
laboratory air if in use regularly. Therefore, refrain from using these agents during application of this procedure.
The use of plastics gloves during pre-treatment may increase the contamination.
The maximum allowed blank level for each phthalate is 80 ng/l with reference to water (see Annex C).
4.3 Interferences in gas chromatography
Phthalates may bleed from the septa of the injector into the gas chromatograph, therefore use septa that are
not likely to contaminate the system.
Fittings of syringes, for example, or equipment and septa of the sampling bottles (see 6.7) may as well contain
phthalates. Therefore make sure that uncontaminated septa are used.
5 Reagents
Use, as far as available, reagents of analytical quality, or better. Use only reagents with negligibly low
concentrations of phthalates and verify by blank determinations and, if necessary, apply additional cleaning
steps.
5.1 Water, having a negligibly low concentration of phthalates.
In some cases, it may be preferable to use surface water instead of distilled water, because the concentration
levels of the blank of surface water can be lower (9.3). Other waters with negligibly low concentrations of
phthalates may be used as well.
5.2 Nitrogen, N of high purity, at least a volume fraction of 99,9 %, for drying and eventually for
2
concentration by evaporation.
5.3 Helium, He of high purity, at least a volume fraction of 99,999 %.
5.4 Operating gases for gas chromatography/mass spectrometry, of high purity and in accordance with
manufacturer's specifications.
5.5 Ethyl acetate, highest purity, C H O .
4 8 2
5.6 Methanol, CH OH.
3
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SIST EN ISO 18856:2005
ISO 18856:2004(E)
5.7 Isooctane, C H (2,2,4-trimethylpentane).
8 18
5.8 Quartz wool, heated to 400 °C for at least 4 h.
5.9 Reversed-phase C18 (RP-C18) material.
Alternative material and commercial glass cartridges may be used, provided the properties are similar to the
material described in this International Standard and the properties are checked in accordance with 4.2.
Check break-through rates prior to starting the analysis and each time a new batch of RP-C18 is used.
5.10 Aluminium oxide, alumina, Al O , neutral, 50 µm to 200 µm, heated to 400 °C for at least 4 h.
2 3
Bring the aluminium oxide to ambient temperature within 6 h. Store in a covered flask. Use within 5 d after
baking.
1)
Alternative materials, such as Florisil or silica may be used, provided their properties and capacity to
separate are similar to aluminium oxide and their properties are checked in accordance with 4.2.
5.11 Internal standards, for example diallyl phthalate, DAlP, C H O ; D4-ring-deuterated dibutyl
14 14 4
phthalate, “D4-DBP”, D4-C H O ; D4-ring-deuterated di(n-octyl) phthalate, “D4-DOP”, D4-C H O ,
16 22 4 24 38 4
13
C -labelled standard (as far as available).
(6 to 12)
5.12 Reference substances of the phthalates, mentioned in Table 1, with defined mass concentrations, for
the preparation of reference solutions for the gas chromatographic procedure.
5.13 Solutions of single substances.
In a 10 ml volumetric flask (6.15), dissolve, for example, 10 mg of each of the reference substances in ethyl
acetate (5.5) and bring to volume with ethyl acetate (mass concentration: 1 g/l).
Store the solutions in glass bottles at −18 °C, protected from light, and check the concentration at least every
three months.
5.14 Stock solution.
In a 10 ml volumetric flask (6.15), add a volume between 100 µl and 500 µl of the single substance solutions
(5.13) and bring to volume with ethyl acetate (mass concentration 10 mg/l to 50 mg/l).
Store the solution in a glass bottle at −18 °C, protected from light, and check the concentration at least every
three months.
5.15 Reference solutions for multipoint calibration.
Prepare solutions by adequate dilution of the stock solution (5.14) and internal standards (5.17) with ethyl
acetate (5.5).
Store the solutions in a glass bottle at −18 °C, protected from light and check the concentration at least every
three weeks.
5.16 Reference solution for the determination of the recovery.
Prepare solutions by adequate dilution of the stock solution (5.14) with ethyl acetate.

1) Florisil is a trade name of prepared magnesium silicate. This information is given for the convenience of users of this
International Standard and does not constitute an endorsement by ISO of this product.
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SIST EN ISO 18856:2005
ISO 18856:2004(E)
5.17 Solution of the internal standards (see Annex D).
5.17.1 Internal standard stock solution of D4-ring-deuterated-di(n-octyl) phthalate (D4-ring-DOP).
Weigh for example 0,1 g of D4-DOP (5.11) in a 10 ml volumetric flask (6.15) filled with about 5 ml of ethyl
acetate (5.5), and bring to volume with ethyl acetate.
5.17.2 Internal standard stock solution of D4-ring-deuterated-dibutyl phthalate (D4-ring-DBP).
Weigh for example 0,1 g of D4-DBP (5.11) in a 10 ml volumetric flask (6.15) filled with about 5 ml of ethyl
acetate (5.5) and bring to volume with ethyl acetate.
5.17.3 Solution I internal standard.
Combine both solutions (5.17.1 and 5.17.2), for example, by dilution 1:100 by pipetting 0,1 ml of each solution
into a 10 ml volumetric flask (6.15) filled with about 5 ml of ethyl acetate (5.5). Bring to volume with ethyl
acetate.
5.17.4 Solution II internal standard.
From Solution I (5.17.3), for example take 250 µl and transfer it to a volumetric flask of 250 ml (6.15) and bring
to volume with ethyl acetate (5.5).
The final concentrations of D4-DBP and of D4-DOP will be 0,1 mg/l in ethyl acetate.
5.17.5 Solution III internal standard.
Transfer 1 ml of Solution I internal standard (5.17.3) to a 10 ml volumetric flask (6.15), filled with 5 ml of ethyl
acetate and bring to volume with ethyl acetate (5.5).
The final concentrations of D4-DBP and of D4-DOP will be 10 mg/l in ethyl acetate.
5.18 Standard solution for the determination of the retention times.
Dilute the solutions of the single substances (5.13) for example 1:1 000 with ethyl acetate (5.5).
NOTE Example of solutions, see Annex D.
6 Apparatus
Equipment or parts likely to come into contact with the water sample or its extract shall be free from phthalates.
This may be achieved by thorough cleaning of all glass apparatus (see 8.1). Examples of equipment to avoid
contamination are given in Annex E.
6.1 Narrow-neck flat bottomed flasks with glass stoppers, preferably brown glass, of 1 000 ml and
2 000 ml capacities.
6.2 Drying oven, capable of being maintained at a temperature of (105 ± 10) °C.
6.3 Muffle furnace, adjustable for temperatures of up to 400 °C, with a capacity of at least 60 l.
6.4 Vacuum device for solid phase extraction (vacubox, extraction box, see E.4).
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SIST EN ISO 18856:2005
ISO 18856:2004(E)
2)
6.5 Stainless steel cock, with stainless steel cone or polytetrafluoroethene (PTFE) cock with a Luer -
connection for separate vacuum connection.
6.6 Wash bottle, for example of 5 l capacity.
6.7 Sampling vial, glass, with inert stopper, e.g. septum, lined with PTFE for storage of the extracts, and
glass sampling bottles, with inert septum, of 2 ml capacity, for storage of the extracts for GC autosampler
operation.
2)
6.8 Glass cartridges, with Luer -cone and conical joint in accordance with ISO 383, DN 14/23 (see E.1).
6.9 Sample reservoir, column, having an inner diameter of 4 cm, length of about 35 cm, conical joint in
accordance with ISO 383, DN 14/23 (e.g. see E.3).
6.10 PTFE-frits for cartridges, of 6 ml capacity.
6.11 Disk to cover the sample reservoir, with an inner diameter of 4,5 cm, and with a circular depression
2
in the range 3,4 cm to 4,5 cm; in the centre of the aluminium disc a hole for the Luer cone, having a diameter
of 0,5 cm (see E.2).
6.12 Aluminium foil, heated to 400 °C.
6.13 Stainless steel reservoir, for storage of smaller glass apparatus.
6.14 Measuring cylinders, of 250 ml and 500 ml capacities.
6.15 Volumetric flasks, of 1 ml, 2 ml, 10 ml, 25 ml and 250 ml capacities.
6.16 Pasteur-pipettes, e.g. 2 ml.
6.17 Syringes, of 2 µl, 5 µl, 10 µl, 50 µl, 100 µl and 500 µl capacities with a maximum permitted error
of ± 2 %.
6.18 Gas chromatograph (GC), with capillary column, temperature-controlled and with mass spectrometric
detection.
6.19 Fused silica capillary columns, with non-polar stationary phase (see Annex F); inner diameter
u 0,32 mm, length about 30 m, film thickness of 0,10 µm to 0,50 µm.
Check the quality of the column, for example by injecting the reference solution (5.16) and ensure that the
separation is satisfactory.
6.20 Glass tubes, graduated, and with a capacity of 10 ml.
6.21 Nitrogen device for drying.

2) Luer cone is a special conical joint and is the trade name of a commercially available product. This information is
given for the convenience of users of this International Standard and does not constitute an endorsement by ISO of this
product.
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SIST EN ISO 18856:2005
ISO 18856:2004(E)
7 Sampling and sample pre-treatment
Collect, preserve and handle samples in accordance with ISO 5667-1, ISO 5667-2 and ISO 5667-3.
Use for sampling pre-treated sampling bottles (6.1 and 8.1) and make sure that the stoppers are pretreated as
well.
Fill the bottles almost completely with the sample.
In general, sampling should be carried out using stainless steel containers or glass vessels.
In order to avoid contamination, do not use any plastics material (tubes and other). If plastics parts in the
sampling apparatus are unavoidable, flush the apparatus with at least five times the volume of the sample. If
applicable, state this step in the test report.
Extract and analyse the sample as soon as possible after sample collection. If storage is unavoidable, store
the samples in the dark at 4 °C no longer than 4 d.
In general, samples are examined without pretreatment, i.e. suspended solids are not removed prior to
analysis.
Prior to analysis, homogenize the sample.
8 Procedure
8.1 Pretreatment of glass apparatus
Clean all glass apparatus used during analysis in the dishwasher with water and subsequently dry in the oven
(6.2) at 105 °C.
Heat the pre-rinsed glass apparatus in the muffle furnace (6.3) using for example the following temperature
programme.
Heat to 100 °C at a rate of 2,5 °C/min; then to 250 °C at a rate of 10 °C/min; finally to 400 °C and maintain
75 min isothermally. Subsequently let the apparatus cool to room temperature within 12 h.
NOTE Glassware for volumetric purposes can change its properties due to the heating process.
Close the cooled glass apparatus (bigger vessels) with the respective stoppers or with aluminium foil (6.12).
Store smaller glass apparatus in decontaminated (heated) and appropriately closed stainless steel containers
(6.13).
In order to avoid losses by adsorption at the walls, rinse the walls with isooctane (5.7) by using Pasteur
pipettes (6.16). Discard the solvent.
Let residual solvent evaporate under a fume hood.
Carry out this deactivation of the surface after heating and cooling or immediately prior to use.
8.2 Extraction
8.2.1 Conditioning of the solid phase material and enrichment
Prepare the cartridges as follows and fill them in the given sequence:
a) place a PTFE frit (6.10) in the cartridge;
b) add 250 mg of RP-C18 material (5.9);
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SIST EN ISO 18856:2005
ISO 18856:2004(E)
c) add heated quartz wool (5.8);
Condition and clean RP-C18 material in the cartridges (6.8) as follows:
 rinse with one bed volume of ethyl acetate (5.5);
 dry with nitrogen for about 10 s (5.2);
 rinse the adsorbent material with two bed volumes of methanol (5.6).
Make sure that the adsorbent material does not run dry after rinsing, e.g. by using the stainless steel cocks
(6.5).
Connect the conditioned cartridges (6.8) with the deactivated reservoir (6.9 and 8.1).
Transfer 250 ml of the sample into the reservoir (6.9), using a measuring cylinder (6.14). Record the volume of
the sample (subscript sam) V .
sam
Alternatively weigh the sample directly into the sample reservoir and cover it with the aluminium disc (6.11).
Close the hole with a pretreated cartridge to reduce contamination by air.
With the aid of a vacubox (6.4), pass the sample through the cartridge (6.8) at a flow rate of about 2 ml/min to
10 ml/min (about 700 hPa). A wash bottle (6.6) may be connected between the vacubox (6.4) and the vacuum
line to collect the sample after passing through the SPE-cartridges and to protect the vacuum line from
entering liquids.
Dry the cartridge with nitrogen (5.2 and 6.21) for about 5 min by connecting the cartridges to a second
vacubox (6.4), thus leading the nitrogen directly over the cartridge.
After drying, place the glass tubes (6.20) into the vacubox, elute the cartridge with 2 ml of internal standard
solution (5.17.4) on the vacubox (6.4) under normal pressure.
After elution of 2 ml, apply a vacuum shortly in order to collect the remaining drops.
The internal standards may be used to eliminate losses by evaporation and injection variations.
Transfer the extract to a GC vial (6.7) and record the volume of extract collected (subscript ex), V , to be
ex
injected. Wrap heated aluminium foil (6.12) around the septum, so that the foil comes between the septum
and the vial, thus avoiding any contamination by phthalates from the septum.
8.2.2 Extract cleaning
In the case of wastewater,
...