SIST EN 13806-1:2025

SLOVENSKI STANDARD
01-maj-2025
Nadomešča:
SIST EN 13806:2002
Živila - Določevanje elementov v sledovih - 1. del: Določevanje celotnega živega
srebra v živilih z atomsko absorpcijsko spektrometrijo (AAS) - Tehnika hladne
pare po razklopu pod pritiskom
Foodstuffs - Determination of trace elements - Part 1: Determination of total mercury in
foodstuffs by atomic absorption spectrometry (AAS) - cold vapour technique after
pressure digestion
Lebensmittel - Bestimmung von Elementspuren - Teil 1: Bestimmung von Quecksilber
mit Atomabsorptionsspektrometrie-(AAS-)Kaltdampftechnik nach Druckaufschluss
Produits alimentaires - Dosage des éléments traces - Partie 1 : Dosage du mercure par
spectrométrie d'absorption atomique par génération de vapeurs froides après digestion
sous pression
Ta slovenski standard je istoveten z: EN 13806-1:2025
ICS:
67.050 Splošne preskusne in General methods of tests and
analizne metode za živilske analysis for food products
proizvode
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 13806-1
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2025
EUROPÄISCHE NORM
ICS 67.050 Supersedes EN 13806:2002
English Version
Foodstuffs - Determination of trace elements - Part 1:
Determination of total mercury in foodstuffs by atomic
absorption spectrometry (AAS) - cold vapour technique
after pressure digestion
Produits alimentaires - Dosage des éléments-traces - Lebensmittel - Bestimmung von Elementspuren - Teil
Partie 1 : Dosage du mercure total dans les produits 1: Bestimmung des Gesamtquecksilbers in
alimentaires par spectrométrie d'absorption atomique Lebensmitteln durch Atomabsorptionsspektrometrie
(SAA) - Génération de vapeurs froides après digestion (AAS) - Kaltdampftechnik nach Druckaufschluss
sous pression
This European Standard was approved by CEN on 17 February 2025.

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, Türkiye 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
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 13806-1:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Principle . 6
5 Reagents . 6
6 Apparatus . 9
7 Sampling . 10
8 Procedure . 10
8.1 Digestion and stabilization . 10
8.2 Cold vapour atomic absorption spectrometry . 10
8.2.1 Spectrometer settings . 10
8.2.2 Cold vapour AAS determination . 10
8.3 Quality control . 10
9 Evaluation . 10
9.1 Calculation . 10
9.2 Limit of quantification . 11
9.3 Precision . 12
9.4 Reproducibility . 12
9.5 Trueness . 12
10 Test report . 13
Annex A (informative) Precision data . 14
Annex B (informative) Alternative stabilizing reagents and short-term stabilization . 16
Bibliography . 17

European foreword
This document (EN 13806-1:2025) has been prepared by Technical Committee CEN/TC 275 “Food
analysis – Horizontal methods”, 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 September 2025, and conflicting national standards shall
be withdrawn at the latest by September 2025.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN-CENELEC shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 13806:2002.
This document includes the following significant technical changes with respect to EN 13806:2002:
— the document has been split up into three separate parts: EN 13806-1 covering the AAS-cold-vapour
technique, EN 13806-2 the AFS-cold-vapour technique and EN 13806-3 the solid sample AAS
technique;
— full technical revision to bring the technical realization up to date with the latest technology;
— stabilization of the digest solution;
— update of statistical data by new interlaboratory study.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations 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, Türkiye and the United
Kingdom.
Introduction
This document has been developed in parallel with EN 13806-2 [1] and EN 13806-3 [2]. All three
methods were validated in parallel in interlaboratory studies with the same scope. They are statistically
compatible in performances. This allows the users of these documents to employ the most
appropriate/available method depending on the purpose of their studies. The statistical parameters of
these standards are presented in the respective documents.
1 Scope
This document specifies a method for the determination of total mercury in foodstuffs by cold vapour
atomic absorption spectrometry (AAS) after pressure digestion.
This method was tested in an interlaboratory study carried out in connection with the pressure digestion
method EN 13805 on seven different materials with a mercury concentration in the range from
0,005 mg/kg to 5,06 mg/kg and successfully validated in the range from 0,015 mg/kg to 5,06 mg/kg.
The following foodstuffs were analysed:
— Saithe (dried);
— Celery (dried);
— Wheat noodle powder;
— Wild mushrooms (dried);
— Pig liver (dried);
— Cacao powder;
— Tuna fish (dried).
The lower limit of the method’s applicability varies depending on the food matrix and the water content
of the foodstuff. It is a laboratory-specific value and is defined by the laboratory when calculating the
limit of quantification (see 9.2).
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.
EN 13804, Foodstuffs - Determination of elements and their chemical species - General considerations and
specific requirements
EN 13805, Foodstuffs - Determination of trace elements - Pressure digestion
3 Terms and definitions
No terms and definitions are listed in this document.
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/
4 Principle
Mercury (Hg) content is determined by AAS-cold-vapour technique in the test solution obtained by
performing the pressure digestion process specified in EN 13805.
The test solution is transferred into the reaction vessel of the mercury analyser to reduce the oxidized
forms of mercury to elemental mercury with bivalent tin or sodium borohydride. The elemental mercury
is then flushed into the cuvette of the AAS instrument using a carrier gas stream. The absorption at the
mercury line of 253,7 nm is used to determine the mercury concentration. In case of very small quantities
of mercury in the test solution, it is recommended to use a technique capable to concentrate the stripped
mercury on a gold/platinum gauze (amalgam technique) prior to determination.
The total content of mercury is understood as the content measured using this specified method. It is
indicated in mg/kg or mg/l, depending on the sample type.
WARNING — The use of this method can involve the application of dangerous substances, actions or
equipment. Nevertheless, the method description cannot mention all dangers possibly involved in its
application. Each operator of the method is responsible for taking the appropriate safety precautions and
to respect the corresponding regulations.
5 Reagents
5.1 General
Unless otherwise specified, “solutions” are understood to be aqueous solutions.
The content of mercury in the chemicals and water shall be low enough not to affect the results.
5.2 Hydrochloric acid, ω = 30 % to 37 %, density = approx. 1,15 g/ml.
5.3 Nitric acid, ω = 65 % to 69 %, density = approx. 1,4 g/ml.
5.4 Diluted nitric acid
Nitric acid (5.3) + water, V + V , approx. 1 + 9.
1 2
5.5 Reducing agent.
5.5.1 General
Tin(II) chloride or sodium borohydride can be used to reduce the oxidized forms of mercury to elemental
mercury (Hg ). However, the alternate use of both reagents is not recommended. The mass
concentrations of the reducing agent solutions can vary depending on the system. Follow the respective
information of the instrument manufacturer.
5.5.2 Tin(II) chloride solution, e.g. ϱ = 100 g/l.
Dissolve 50 g of tin(II) chloride, SnCI • 2 H 0, in approx. 100 ml of hydrochloric acid (5.2) in a 500 ml
2 2
volumetric flask and fill up to the mark with water. The solution shall be prepared freshly before use.
NOTE 1 The required concentration of tin(II) chloride depends on the analysis system and the concentration of
nitric acid in the test solution. Too low concentrations of tin(II) chloride could lead to insufficient recoveries.
NOTE 2 Tin(II) chloride ages quickly, visible in light yellow precipitates of tin(IV) oxides. In case of higher
concentrations of tin(II) chloride, these precipitates occur more frequently.
NOTE 3 If necessary, the tin(II) chloride solution can be flushed with argon gas in order to remove any possible
traces of mercury.
5.5.3 Sodium borohydride solution, e.g. at a concentration of ϱ = 3 g/l.
Dissolve 1,5 g of sodium borohydride together with 0,5 g of sodium hydroxide pellets in water in a 500 ml
volumetric flask and fill up to the mark.
This solution shall be prepared freshly and filtered before use.
WARNING — It is imperative to observe the safety instructions when working with sodium borohydride.
In combination with acids, sodium borohydride produces hydrogen. This can lead to an explosive mix of
air and hydrogen. A fume hood shall be available.
5.6 Carrier solution
Diluted hydrochloric acid (prepared from 5.2, e.g. ω = 3 %) is used as the carrier solution.
The mass concentration of the carrier solution can vary depending on the instrument. Observe the
respective information of the instrument manufacturer.
5.7 Stabilization
The standard, calibration, zero-point and sample digestion solutions are stabilized with hydrochloric acid
(5.2). For hydrochloric acid, it is recommended to use a sufficient concentration. In the validation study,
the mass fraction of approx. 1 % in the solution was appropriate. An example is provided in Table 1 and
Table 2.
Alternatively, other stabilizing reagents may be used (see Annex B).
5.8 Mercury stock solution, with a concentration of ϱ = 1 000 mg/l.
The stock solution is commercially available. It is recommended to use certified stock solutions.
5.9 Mercury standard solution
The standard solutions are prepared from the stock solution (5.8) in several dilution steps.
For this purpose, fill approx. 20 ml of water into a 100 ml volumetric flask, add the necessary amount of
stabilizing reagent (5.7) and mix. After the mixture has cooled down to room temperature, the stock (5.8)
or standard solution (see Table 1) is added into the flask and filled-up to the mark with water.
The standard solutions are stable for at least one month.
Table 1 — Example for the preparation of Hg standard solutions in 100 ml volumetric flasks
Fill up to the
Standard solution Stabilization Initial solution mark with
water to
[Hg concentration]
Standard solution 1
3 ml hydrochloric 1 ml Hg stock
100 ml
acid (5.2) solution (5.8)
[10 mg/l]
Standard solution 2
3 ml hydrochloric 1 ml standard
100 ml
acid (5.2) solution 1
[0,1 mg/l]
5.10 Zero-point solution
Fill approx. 20 ml of water into a 100 ml volumetric flask, add the necessary amounts of stabilizing and
digestion reagents (e.g. 3 ml of hydrochloric acid (5.2) and 10 ml of nitric acid (5.3)), mix and fill up to
the mark with water.
The zero-point solution is used as calibration blank (see Table 2) and might be used for further dilutions
of the digestion solutions in case of excessive concentrations in the samples.
5.11 Mercury calibration solutions
The acid concentrations in the calibration solutions and in the zero-point solution (5.10) shall correspond
to the acid concentration in the test solution. Even at higher concentrations, mercury calibration solutions
do not remain stable for a long time and therefore shall be prepared freshly every working day. If possible,
the concentrations of the calibration solutions are to be selected in such a way that the linear range of the
calibration function is not exceeded. It is recommended to use at least three calibration solutions with
different concentrations (see examples in Table 2).
For this purpose, fill approx. 20 ml of water into a 100 ml volumetric flask, add the necessary amounts of
stabilizing and digestion reagents according to Table 2 and mix. After the mixture has cooled down to
room temperature, add standard solution 2 in accordance with Table 2 into the flask and fill up to the
mark with water.
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