oSIST prEN ISO 16703:2024

Environmental Solid Matrices - Determination of hydrocarbon content in the range of C10 to C40 by gas chromatography (ISO/DIS 16703:2024)

ISO 16703:2004 specifies a method for the quantitative determination of the mineral oil (hydrocarbon) content in field-moist soil samples by gas chromatography.
The method is applicable to mineral oil contents (mass fraction) between 100 mg/kg and 10 000 mg/kg soil, expressed as dry matter, and can be adapted to lower detection limits.
ISO 16703:2004 is applicable to the determination of all hydrocarbons with a boiling range of 175 °C to 525 °C, n-alkanes from C10H22 to C40H82, isoalkanes, cycloalkanes, alkylbenzenes, alkylnaphthalenes and polycyclic aromatic compounds, provided that they are not absorbed on the specified column during the clean-up procedure.
ISO 16703:2004 is not applicable to the quantitative determination of hydrocarbons < C10 originating from gasolines.
On the basis of the peak pattern of the gas chromatogram obtained, and of the boiling points of the individual n-alkanes listed in Annex B, the approximate boiling range of the mineral oil and some qualitative information on the composition of the contamination can be achieved.

Bodenqualität- Bestimmung des Gehalts an Kohlenwasserstoffen im Bereich C10 bis C40 durch Gaschromatographie (ISO/DIS 16703:2024)

Matrices solides environnementales - Dosage des hydrocarbures de C10 à C40 par chromatographie en phase gazeuse (ISO/DIS 16703:2024)

L'ISO 16703:2004 spécifie une méthode de dosage quantitatif par chromatographie en phase gazeuse des huiles minérales (hydrocarbures) contenues dans des échantillons de sol bruts.
La méthode est applicable à des teneurs en huiles minérales (fraction massique) comprises entre 100 mg/kg et 10 000 mg/kg de sol, exprimées sous forme de matière sèche, et peut être adaptée à des limites inférieures de détection.
L'ISO 16703:2004 est applicable au dosage de tous les hydrocarbures ayant un domaine d'ébullition compris entre 175 °C et 525 °C, des n-alcanes entre C10H22 et C40H82, des isoalcanes, des cycloalcanes, des alkylbenzènes, des alkylnaphtalènes et des composés aromatiques polycycliques, à condition qu'ils ne soient pas absorbés sur la colonne spécifiée pendant l'étape de purification.
L'ISO 16703:2004 n'est pas applicable au dosage quantitatif des hydrocarbures < C10 provenant des essences.
Compte tenu de la forme des pics du chromatogramme en phase gazeuse obtenu et du point d'ébullition des différents n-alcanes indiqués à l'Annexe B, il est possible de déterminer le domaine d'ébullition approximatif des huiles minérales et d'obtenir quelques informations qualitatives sur la composition des polluants.

Trdni matriksi v okolju - Določanje ogljikovodikov v območju C10 do C40 s plinsko kromatografijo (ISO/DIS 16703:2024)

General Information

• Status: Not Published
• Public Enquiry End Date: 19-Nov-2024
• ICS: 13.080.10 - Chemical characteristics of soils
• Technical Committee: KAT - Soil quality
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 17-Sep-2024
• Due Date: 04-Feb-2025
• Completion Date: 04-Nov-2024
• Ref Project: prEN ISO 16703 - Environmental Solid Matrices - Determination of hydrocarbon content in the range of C10 to C40 by gas chromatography (ISO/DIS 16703:2024)

Relations

• Revises: SIST EN ISO 16703:2011 - Soil quality - Determination of content of hydrocarbon in the range C10 to C40 by gas chromatography (ISO 16703:2004)
• Effective Date: 01-Nov-2024

Overview

prEN ISO 16703 (ISO/DIS 16703:2024) - Environmental Solid Matrices - specifies a gas‑chromatographic method for the quantitative determination of hydrocarbon (mineral oil) content in environmental solid matrices (soil and waste) in the carbon range C10 to C40. The method targets hydrocarbons with an approximate boiling range of 175 °C to 525 °C and is applicable to field‑moist samples expressed on a dry‑matter basis. Typical analytical scope covers mass fractions from 100 mg/kg to 10 000 mg/kg (adaptable to lower detection limits).

Key topics and requirements

• Analyte range: n‑alkanes C10–C40, isoalkanes, cycloalkanes, alkylbenzenes, alkylnaphthalenes and polycyclic aromatics that elute between n‑decane and n‑tetracontane on a non‑polar capillary column. Volatile hydrocarbons (< C10, e.g. petrol) are not reliably quantified.
• Sample preparation: Extraction of homogenized (field‑moist) samples with an acetone/hexane‑like solvent (2+1), separation of organic layer, water washes, and clean‑up on Florisil to remove polar interferences.
• Chromatography: Capillary gas chromatography with flame ionization detection (GC‑FID). Total peak area between retention windows for n‑decane and n‑tetracontane is used for quantification.
• Calibration & QC: External calibration against mineral oil standards (equal amounts of two mineral oils), plus blanks, recovery checks, system performance tests and repeatability/validation procedures as described in the standard.
• Practical notes: For plastic‑containing samples avoid acetone in extraction to prevent false‑high results; lower detection limits can be achieved by large‑volume injection or concentration of final extract.
• Informative annexes: Examples of chromatograms, boiling‑range estimation (Annex B), product‑type determination (Annex D), aqueous waste handling (Annex E) and validation data.

Applications and users

• Environmental testing and soil quality laboratories performing petroleum hydrocarbon contamination assessments.
• Site investigation and remediation consultants quantifying mineral oil contamination for risk assessment and regulatory compliance.
• Waste management and contaminated land regulators requiring a harmonized GC‑FID method for reporting hydrocarbon content (C10–C40).
• Research groups studying long‑chain hydrocarbon pollution in soils and sediments.

Related standards

• ISO 14507 (sample pretreatment)
• ISO 18512 (sample storage)
• ISO 11465 (dry matter/water content)
• EN 15934 (dry matter calculation)
• ISO 8466‑1 (calibration and evaluation of analytical methods)

Keywords: ISO 16703, prEN ISO 16703, hydrocarbon content, C10 to C40, gas chromatography, GC‑FID, soil quality, mineral oil, Florisil clean‑up, environmental solid matrices.

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2024
Trdni matriksi v okolju - Določanje ogljikovodikov v območju C10 do C40 s plinsko
kromatografijo (ISO/DIS 16703:2024)
Environmental Solid Matrices - Determination of hydrocarbon content in the range of C10
to C40 by gas chromatography (ISO/DIS 16703:2024)
Bodenqualität- Bestimmung des Gehalts an Kohlenwasserstoffen im Bereich C10 bis
C40 durch Gaschromatographie (ISO/DIS 16703:2024)
Matrices solides environnementales - Dosage des hydrocarbures de C10 à C40 par
chromatographie en phase gazeuse (ISO/DIS 16703:2024)
Ta slovenski standard je istoveten z: prEN ISO 16703
ICS:
13.080.10 Kemijske značilnosti tal Chemical characteristics of
soils
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 16703
ISO/TC 190/SC 3
Environmental Solid Matrices —
Secretariat: DIN
Determination of hydrocarbon
Voting begins on:
content in the range of C to C by
10 40
2024-09-03
gas chromatography
Voting terminates on:
ICS: ISO ics
2024-11-26
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
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Reference number
ISO/DIS 16703:2024(en)
DRAFT
ISO/DIS 16703:2024(en)
International
Standard
ISO/DIS 16703
ISO/TC 190/SC 3
Environmental Solid Matrices —
Secretariat: DIN
Determination of hydrocarbon
Voting begins on:
content in the range of C to C by
10 40
gas chromatography
Voting terminates on:
ICS: ISO ics
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2024
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
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Published in Switzerland Reference number
ISO/DIS 16703:2024(en)
ii
ISO/DIS 16703:2024(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Principle . 2
5 Reagents . 2
6 Equipment . 4
7 Sample conservation and pretreatment . 4
8 Procedure . 5
8.1 Blank .5
8.2 Extraction and clean-up .5
9 Determination by gas chromatography . 6
9.1 Test of the performance of the gas chromatographic system .6
9.2 Test of repeatability .6
9.3 Initial calibration .6
9.4 Working calibration .6
9.5 Validity check of the calibration function .6
9.6 Measurement .6
9.7 Integration.6
10 Calculation . 7
11 Quality control . 8
11.1 Suitability check of the clean-up procedure .8
11.2 Recovery of the hydrocarbon standard solution .8
11.3 Quality control sample .9
12 Performance characteristics . 9
13 Test report . 9
Annex A (informative) Examples of gas chromatograms of hydrocarbon standard and selected
samples .10
Annex B (informative) Determination of the boiling range of mineral oil hydrocarbons from
the gas chromatogram . 14
Annex C (informative) Validation data .16
Annex D (informative) Determination of product type .18
Annex E (informative) Aqueous liquid waste .22
Bibliography .23

iii
ISO/DIS 16703:2024(en)
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,
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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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO [had/had not] received notice of
(a) patent(s) which may be required to implement this document. However, implementers are cautioned that
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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 3, Chemical
and physical characterization.
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.

iv
DRAFT International Standard ISO/DIS 16703:2024(en)
Environmental Solid Matrices — Determination of
hydrocarbon content in the range of C to C by gas
10 40
chromatography
1 Scope
This International Standard specifies a method for the quantitative determination of the mineral oil
(hydrocarbon) (C to C ) content in soil and waste samples by gas chromatography.
10 40
The method is applicable to mineral oil contents (mass fraction) between 100 mg/kg and 10 000 mg/kg soil,
expressed as dry matter, and can be adapted to lower limits of detection.
Using this standard all hydrocarbons with a boiling range of approximately 175 °C to 525 °C, e.g. n-alkanes
from C H to C H , isoalkanes, cycloalkanes, alkyl benzenes, alkyl naphthalenes and polycyclic aromatic
10 22 40 82
compounds are determined as hydrocarbons, provided they do not adsorb on the Florisil column during
clean-up.
The standard can also be applied to determine any fraction in-between the range n-C to n-C .
10 40
Volatile hydrocarbons cannot be quantitatively determined using this standard. This will affect the
determination of some common hydrocarbon fuels, e.g. petrol.
NOTE 1 On the basis of the peak pattern of the gas chromatogram (see Annex D) and of the boiling points of the
individual n-alkanes listed in Annex B the approximate boiling range of the hydrocarbons and some qualitative
information on the nature of the hydrocarbons can be obtained.
NOTE 2 At the moment there is no sufficient information on how to handle organic liquid wastes (e.g. by-product of
a manufacturing process, oils and greases) for the analysis of hydrocarbons.
NOTE 3 Aqueous liquid waste samples can be analyzed in accordance with EN ISO 9377-2 or the procedure specified
in Annex E.
NOTE 4 Plastic containing samples must be treated by a hexane-like extraction solvent without usage of acetone in
order to avoid overfindings (false-high content).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 14507, Soil quality — Pretreatment of samples for determination of organic contaminants
ISO 18512, Soil quality — Guidance on long and short term storage of soil samples
ISO 11465:1993, Soil quality — Determination of dry matter and water content on a mass basis —
Gravimetric method
EN 15934, Sludge, treated biowaste, soil and waste — Calculation of dry matter fraction after determination of
dry residue or water content
ISO 8466-1, Water quality — Calibration and evaluation of analytical methods — Part 1: Linear calibration
function
ISO/DIS 16703:2024(en)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
hydrocarbon content by gas chromatography
sum of compounds that are extractable with acetone/hexane-like solvent (2+1) from environmental solid
matrices, that do not adsorb on a specified single Florisil column cleanup and can be chromatographed on
a non-polar capillary column with retention times between those of n-decane (C H ) and n-tetracontane
10 22
(C H )
40 82
Note 1 to entry: Substances that comply with this definition are mainly non-polar long chain or branched aliphatic,
alicyclic, alkyl substituted aromatic or polycyclic aromatic compounds.
Note 2 to entry: This definition differs from that given by utilizing a gravimetric approach (e.g. EN 14345).
Note 3 to entry: Non-polar and weakly polar compounds (e.g. halogenated hydrocarbons) and high contents of more
polar compounds, e.g. animal and vegetable fats and oils, may exceed the adsorption capacity of the Florisil used.
4 Principle
A known amount of the homogenized sample is extracted by mechanical shaking or sonication with
acetone/hexane-like solvent. The organic layer is separated and washed twice with water. Polar compounds
are removed by chromatography on Florisil. An aliquot of the purified extract is analyzed by capillary gas
chromatography with flame ionization detection.
The total peak area between the retention time window standards n-decane and n-tetracontane is measured
and the amount of hydrocarbons in the sample is quantified against an external standard consisting of equal
amounts of two different types of mineral oil.
NOTE 1 hexane-like solvent can be understood as n-heptane, or other non-polar solvent (e.g. petroleum ether,
cyclohexane).
NOTE 2 If lower detection limits are required, large-volume injection or concentration of the final extract can be
applied.
5 Reagents
In general, all reagents shall be reagent grade and suitable for their specific purposes.
5.1 Acetone, (CH ) CO.
3 2
5.2 hexane-like solvent as n-Heptane, C H ; alternatively, other hexane-like solvents after proving
7 16
suitability (range of boiling point 60 °C-100 °C).
5.3 Florisil for preparation of clean-up column, particle size 150 µm to 250 µm (60 mesh to 100 mesh),
heated for at least 16 h at 140 °C and stored in a desiccator over a molecular sieve.
NOTE Commercially available cartridges containing Florisil and sodium sulfate are also applicable.
5.4 Anhydrous sodium sulfate (Na SO ), heated for at least 2 h at 550 °C. Afterwards the sodium sulfate
2 4
should be stored under dry conditions (e.g. a desiccator).

ISO/DIS 16703:2024(en)
5.5 Test solution of stearyl stearate (C H O ); n-octadecanoic acid octadecyl ester.
36 72 2
Dissolve e.g. (100 ± 1) mg of n-octadecanoic acid octadecyl ester in 100 ml hexane-like solvent [5.2] to yield
a concentration of 1 mg/ml. The solution is stable for 6 months when stored in a refrigerator between 1 °C
and 5 °C.
5.6 Retention-time window (RTW) standard solution, containing n tetracontane and n-decane.
Retention-time window (RTW) standard solution is the range-defining standard solution. Weigh (30 ± 1) mg
of n-tetracontane into a 1 l volumetric flask, dissolve completely in an appropriate volume of n-heptane (6.2),
add 30 µl of n-decane (about 21 mg), mix well, fill up to volume with hexane-like solvent and homogenize.
This solution shall be used for all dilution steps of the hydrocarbon standard (6.7).
Store at room temperature.
NOTE n-Tetracontane is only moderately soluble in hexane-like solvent. Slight warm-up and/or sonicate to
accelerate the dissolution process.
5.7 Hydrocarbon standard solution for calibration
Mix approximately equal masses of two different types of mineral oil. Weigh accurately this mixture and
dissolve in the RTW standard solution (6.6) to give a hydrocarbon mass concentration of about 8 g/l.
The first oil type should show discrete peaks (e.g. a diesel fuel) in the gas chromatogram, as can be seen in
Figure A.1 (left part of the chromatogram). The second type should have a boiling range higher than the
first one, and should show a hump in the gas chromatogram, as can be seen in Figure A.1 (right part of the
chromatogram). A suitable oil of this type is for example a lubricating oil without any additives.
The calibration solutions can be prepared by diluting an aliquot of this standard solution with different
volumes of the RTW standard solution (6.6).
5.8 Calibration control solution
Prepare an independent control solution in accordance with (6.7) using a hydrocarbon concentration about
in the middle of the working range.
5.9 System-performance standard solution
Prepare a mixture of equal amounts, on a mass basis, of the n-alkanes with even carbon numbers from C
to C , dissolved in hexan-like solvent [5.2], to give a concentration of about 50 mg/l of each n-alkane. Store
at room temperature.
This solution is used to verify the suitability of the gas chromatographic system for the resolution of
n-alkanes as well as for the detector response.
NOTE This solution is in addition used to give information of the retention times of the n-alkanes to characterize
the hydrocarbons in the samples (c.f. Annex D).
5.10 Solution for definition of retention times
For all fraction based on even carbon numbers, the system performance standard solution (6.9) can be
used for determination of retention times. If fractions are to be determined with odd carbon numbers (e.g.
>C -C ), a standard solution containing at least all relevant n-alkanes have to be applied.
10 25
5.11 Preparation of the clean-up column
A plug of pre-washed glass wool or a PTFE frit is pushed down into the column [6.9]. Then, successively 2 g
Florisil [5.3] and 2 g sodium sulfate [6.4] are added. The column shall be prepared immediately before use
or stored in a dry environment (e.g. desiccator). In addition, commercially available columns can be used, if
suitability has been proven.
ISO/DIS 16703:2024(en)
After proving suitability, a miniaturization of the cleanup can be applied, and the ratio used extract to
Florisil/sodium sulfate must remain the same (10:2:2; e.g. 5 mL with 1 g Florisil and 1 g sodium sulfate).
6 Equipment
6.1 Standard laboratory glassware, which shall be treated at high temperatures or rinsed with acetone
(5.1) and dried before use.
6.2 Devices for extraction, mechanical shaker (at least 120 rpm) or ultrasonic bath.
6.3 Gas chromatograph, equipped with a non-discriminating injector, a flame ionization detector (FID)
and a temperature programmable oven.
NOTE The use of a large-volume injection system can improve the limit of detection considerably.
6.4 Capillary column, fused silica column with suitable stationary phase and dimensions, e.g.
stationary phase: non-polar (e.g. immobilised 100 % dimethyl polysiloxane, 95 %-dimethyl-5 %-diphenyl
polysiloxane, modified siloxane polymer, etc.);
length: 2 to 20 m;
internal diameter: 0,1 mm to 0,32 mm;
film thickness: 0,1 µm to 1,0 µm.
The column should give a base-line separation of the n-alkanes when the system performance standard
solution [6.9] is run.
NOTE 1 Thermally stable low bleed columns should be preferred.
NOTE 2 The use of a pre-column, e.g. wide-bore (0,53 mm internal diameter) deactivated fused silica of at least 2 m
of length is recommended.
6.5 Data system, capable of integrating the total area of the chromatogram, compensating for column
bleed and reintegrating after defining a new baseline.
6.6 Glass extraction vessel of volume at least 100 ml, with screw caps provided with a septum coated
with polytetrafluoroethylene (PTFE).
6.7 Glass tube, e.g. 25 ml, with ground glass stopper or screw caps incorporating a septum coated with
polytetrafluoroethylene (PTFE).
6.8 Separation funnel, at least 500 ml, with a ground glass stopper.
6.9 Chromatography column for clean-up, glass columns of about 10 mm internal diameter. Preferably,
the upper part of the column should be widened to use as solvent reservoir and the lower part to be narrowed
to form a tip.
Plastic columns can be used if they meet the requirements given in chapter 8.2.
7 Sample conservation and pretreatment
Storage and pretreatment should be according to ISO 18512, if not otherwise specified.
Before analysis the samples shall be homogenized.

ISO/DIS 16703:2024(en)
Drying of the sample at max. 40 °C can be applied, if losses of hydrocarbons can be neglected. If drying is
applicable, freeze drying is preferable.
8 Procedure
8.1 Blank
With each series of samples, carry out a blank determination according to 8.3 using all reagents in identical
amounts but without a sample. If blank values are unusually high (more than 50 % of the lowest value of
interest), every step in the procedure shall be checked to determine the cause of these high blanks.
8.2 Extraction and clean-up
Weigh an exact amount of about e.g. 20 g of the homogenized field-moist or pretreated soil sample into a glass
extraction vessel (7.7) and add e.g. 40 ml of acetone with a precision of +/- 1 mL (6.1).
...