CEN/TS 17786-2:2022
(Main)Inorganic micronutrient fertilizers - Determination of the chelated micronutrient content and the chelated fraction of micronutrients - Part 2: Determination of EDTA, DTPA, HEEDTA, IDHA or EDDS
Inorganic micronutrient fertilizers - Determination of the chelated micronutrient content and the chelated fraction of micronutrients - Part 2: Determination of EDTA, DTPA, HEEDTA, IDHA or EDDS
This document specifies a method for the determination of the chelated fraction of micronutrients for fertilizers containing one or many micronutrients chelated by EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS in fertilizers.
This method is used for inorganic micronutrient fertilizers when micronutrients are chelated only by EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS or for mixtures in which EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS is one of the chelating agents.
The method is applicable to all inorganic micronutrient fertilizers containing EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS as chelating agent for contents > 0,1 % (w/w).
The method is based on ICP or AAS measurement of the concentration of micronutrients according to EN 16963 or EN 16965 after water extraction according to EN 16962 and LC measurement of the chelating agents according to EN 15950, EN 13368-1 and EN 13368-3.
Anorganische Spurennährstoff-Düngemittel - Bestimmung des Gehaltes an chelatisierten Spurennährstoffen und des chelatisierten Anteils an Spurennährstoffen - Teil 2: Bestimmung von EDTA, DTPA, HEEDTA, IDHA oder EDDS
Dieses Dokument legt ein Verfahren zur Bestimmung des Gehalts an chelatisiertem Eisen sowie des chelatisierten Anteils an Eisen in UVCB-Chelaten, EDDHA, EDDHMA, HBED und EDDHSA in anorganischen Spurennährstoff-Düngemitteln durch Behandlung mit einem Kationenaustauschharz fest.
Die Bestimmungsgrenze des Gehalts an chelatisiertem Eisen hängt stark von der spezifischen elektrischen Leitfähigkeit der Probe und der Menge des vorhandenen Nährstoffs ab und variiert zwischen 0,005 % in einfachen Matrices mit großen Mengen an Spurennährstoffen und 0,5 % in komplexeren Fällen (siehe 9.1).
Engrais inorganiques à base d'oligo-éléments - Détermination de la teneur en oligo-éléments chélatés et de la fraction chélatée des oligo-éléments - Partie 2 : Dosage de l'EDTA, du DTPA, du HEEDTA, de l'IDHA ou de l'EDDS
Le présent document spécifie une méthode pour la détermination de la fraction chélatée des oligo-éléments pour les engrais contenant un ou plusieurs oligo-éléments chélatés par de l’EDTA, du DTPA, du HEEDTA, de l’IDHA ou du [S,S]-EDDS dans les engrais.
Cette méthode est utilisée pour les engrais inorganiques à base d’oligo-éléments lorsque les oligo-éléments sont chélatés uniquement par de l’EDTA, du DTPA, du HEEDTA, de l’IDHA ou du [S,S]-EDDS ou pour des mélanges dans lesquels l’EDTA, le DTPA, le HEEDTA, l’IDHA ou le [S,S]-EDDS est l’un des agents chélatants.
La méthode est applicable à tous les engrais inorganiques à base d’oligo-éléments contenant de l’EDTA, du DTPA, du HEEDTA, de l’IDHA ou du [S,S]-EDDS comme agent chélatant pour des teneurs > 0,1 % (w/w).
La méthode est basée sur un dosage par ICP ou par AAS de la concentration en oligo-éléments conformément à l’EN 16963 ou l’EN 16965 après extraction à l’eau conformément à l’EN 16962, et sur un dosage par LC des agents chélatants conformément à l’EN 15950, l’EN 13368-1 et l’EN 13368-3.
Anorganska gnojila z mikrohranili - Določanje vsebnosti kelatiranih mikrohranil in deleža kelatiranih mikrohranil - 2. del: Določevanje EDTA, DTPA, HEEDTA, IDHA ali EDDS
Ta dokument navaja metodo za določanje kelatiranega deleža mikrohranil za gnojila, kadar je eno ali več mikrohranil v gnojilih kelatirano z EDTA, DTPA, HEEDTA, IDHA ali [S,S]-EDDS.
Ta metoda se uporablja za anorganska gnojila z mikrohranili, kadar so mikrohranila kelatirana samo z EDTA, DTPA, HEEDTA, IDHA ali [S,S]-EDDS, ali za mešanice, v katerih je EDTA, DTPA, HEEDTA, IDHA ali [S,S]-EDDS eno od sredstev za kelatiranje.
Metoda je uporabna za vsa anorganska gnojila z mikrohranili, ki vsebujejo EDTA, DTPA, HEEDTA, IDHA ali [S,S]-EDDS kot sredstvo za kelatiranje za vsebnosti > 0,1 % (g/100 g).
Metoda temelji na meritvi ICP ali AAS koncentracije mikrohranil v skladu s standardom EN 16963 ali EN 16965 po vodni ekstrakciji v skladu s standardom EN 16962 in meritvi LC sredstev za kelatiranje v skladu s standardi EN 15950, EN 13368-1 in EN 13368-3.
General Information
- Status
- Published
- Publication Date
- 05-Apr-2022
- Technical Committee
- CEN/TC 260 - Fertilizers and liming materials
- Drafting Committee
- CEN/TC 260/WG 5 - Determination of chelating agents
- Current Stage
- 9060 - Closure of 2 Year Review Enquiry - Review Enquiry
- Start Date
- 02-Dec-2025
- Completion Date
- 02-Dec-2025
Relations
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Referred By
EN 3847:2019 - Aerospace series - Paints and varnishes - Determination of sedimentation rating - Effective Date
- 28-Jan-2026
- Referred By
CEN/TS 17791:2022 - Inorganic fertilizers - Determination of chelating and complexing agents - Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
Overview
CEN/TS 17786-2:2022 specifies a standardized method for the determination of the chelated fraction of micronutrients in inorganic micronutrient fertilizers that contain one or more chelating agents: EDTA, DTPA, HEEDTA, IDHA, or [S,S]-EDDS. This technical specification supports accurate assessment and compliance verification for products marketed within regulatory frameworks, such as the EU Fertilising Products Regulation.
Chelated micronutrients are essential in ensuring efficient plant nutrient uptake, particularly for iron, manganese, zinc, copper, molybdenum, and boron. By establishing a uniform test method for quantifying chelated micronutrient content, this standard helps guarantee agrochemical product quality, regulatory compliance, and protects both agricultural productivity and environmental health.
Key Topics
- Chelating Agents Covered: The standard applies specifically to fertilizers using the chelating agents EDTA, DTPA, HEEDTA, IDHA, or [S,S]-EDDS and is suitable for any mixture where these agents are present.
- Applicability: This method is relevant for inorganic micronutrient fertilizers containing above 0.1% (w/w) of the specified chelating agents.
- Analytical Methods:
- Micronutrient Content: Measurement by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) or Flame Atomic Absorption Spectrometry (FAAS), as detailed in EN 16963 and EN 16965, following water extraction (EN 16962).
- Chelating Agent Content: Quantified via chromatography methods specified in EN 13368-1 (for EDTA, HEEDTA, DTPA), EN 13368-3 ([S,S]-EDDS), and EN 15950 (IDHA).
- Expression of Results: The chelated fraction is calculated as the ratio of the chelating agent(s) content to the water-soluble micronutrient content, expressed as a percentage.
- Quality Assurance: The procedure includes requirements for reagent purity, apparatus qualifications, and recommendations for sampling and sample preparation.
Applications
Implementing CEN/TS 17786-2:2022 is highly valuable for:
- Fertilizer Manufacturers: Ensuring accurate product labeling, consistency across batches, and meeting market requirements for chelated micronutrient content in line with EU and international standards.
- Testing Laboratories: Providing a harmonized, reproducible method for determining micronutrient chelation, supporting routine quality control and regulatory submissions.
- Regulatory Authorities: Assisting with inspection, monitoring, and enforcement of compliance for fertilizers marketed in the European Union and beyond.
- Agricultural Sector: Offering assurance to growers regarding product quality and the effectiveness of nutrient delivery, thereby supporting crop yield optimization and sustainable production.
Related Standards
- EN 16962: Extraction of water-soluble micronutrients in fertilizers.
- EN 16963 / EN 16965: Determination of micronutrient elements via ICP-AES and FAAS.
- EN 13368-1 / EN 13368-3: Chromatographic determination of specific chelating agents.
- EN 15950: HPLC determination of IDHA in fertilizers.
- EN 12944-1 / EN 12944-2: Vocabulary of general and fertilizer-specific terms.
- EN 1482-1 / EN 1482-2: Methods for sampling and sample preparation of fertilizers.
By referencing and applying these harmonized analytical methods, stakeholders can ensure robust, reliable, and internationally accepted measurement of chelated micronutrient content. Adoption of CEN/TS 17786-2:2022 strengthens traceability, supports regulatory conformity, and fosters confidence in the fertilizer supply chain.
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Frequently Asked Questions
CEN/TS 17786-2:2022 is a technical specification published by the European Committee for Standardization (CEN). Its full title is "Inorganic micronutrient fertilizers - Determination of the chelated micronutrient content and the chelated fraction of micronutrients - Part 2: Determination of EDTA, DTPA, HEEDTA, IDHA or EDDS". This standard covers: This document specifies a method for the determination of the chelated fraction of micronutrients for fertilizers containing one or many micronutrients chelated by EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS in fertilizers. This method is used for inorganic micronutrient fertilizers when micronutrients are chelated only by EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS or for mixtures in which EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS is one of the chelating agents. The method is applicable to all inorganic micronutrient fertilizers containing EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS as chelating agent for contents > 0,1 % (w/w). The method is based on ICP or AAS measurement of the concentration of micronutrients according to EN 16963 or EN 16965 after water extraction according to EN 16962 and LC measurement of the chelating agents according to EN 15950, EN 13368-1 and EN 13368-3.
This document specifies a method for the determination of the chelated fraction of micronutrients for fertilizers containing one or many micronutrients chelated by EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS in fertilizers. This method is used for inorganic micronutrient fertilizers when micronutrients are chelated only by EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS or for mixtures in which EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS is one of the chelating agents. The method is applicable to all inorganic micronutrient fertilizers containing EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS as chelating agent for contents > 0,1 % (w/w). The method is based on ICP or AAS measurement of the concentration of micronutrients according to EN 16963 or EN 16965 after water extraction according to EN 16962 and LC measurement of the chelating agents according to EN 15950, EN 13368-1 and EN 13368-3.
CEN/TS 17786-2:2022 is classified under the following ICS (International Classification for Standards) categories: 65.080 - Fertilizers. The ICS classification helps identify the subject area and facilitates finding related standards.
CEN/TS 17786-2:2022 has the following relationships with other standards: It is inter standard links to EN 13368-1:2014, EN 16965:2018, EN 12944-2:1999, EN 12944-1:1999, EN 13368-3:2017, EN 16963:2018, EN 16962:2018, EN 15950:2010, CEN/TS 17783:2022, EN 3847:2019, CEN/TS 17791:2022, CEN/TS 17782:2022, CEN/TS 17764:2022. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
CEN/TS 17786-2:2022 is associated with the following European legislation: EU Directives/Regulations: 2019/1009; Standardization Mandates: M/564. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.
CEN/TS 17786-2:2022 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-februar-2023
Anorganska gnojila z mikrohranili - Določanje vsebnosti kelatiranih mikrohranil in
deleža kelatiranih mikrohranil - 2. del: Določevanje EDTA, DTPA, HEEDTA, IDHA ali
EDDS
Inorganic micronutrient fertilizers - Determination of the chelated micronutrient content
and the chelated fraction of micronutrients - Part 2: Determination of EDTA, DTPA,
HEEDTA, IDHA or EDDS
Anorganische Spurennährstoff-Düngemittel - Bestimmung des Gehaltes an chelatisierten
Spurennährstoffen und des chelatisierten Anteils an Spurennährstoffen - Teil 2:
Bestimmung von EDTA, DTPA, HEEDTA, IDHA oder EDDS
Engrais inorganiques à base d'oligo-éléments - Détermination de la teneur en oligo-
éléments chélatés et de la fraction chélatée des oligo-éléments - Partie 2 : Dosage de
l'EDTA, du DTPA, du HEEDTA, de l'IDHA ou de l'EDDS
Ta slovenski standard je istoveten z: CEN/TS 17786-2:2022
ICS:
65.080 Gnojila Fertilizers
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
CEN/TS 17786-2
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
April 2022
TECHNISCHE SPEZIFIKATION
ICS 65.080
English Version
Inorganic micronutrient fertilizers - Determination of the
chelated micronutrient content and the chelated fraction
of micronutrients - Part 2: Determination of EDTA, DTPA,
HEEDTA, IDHA or EDDS
Engrais inorganiques à base d'oligo-éléments - Anorganische Spurennährstoffdüngemittel -
Détermination de la teneur en oligo-éléments chélatés Bestimmung des Gehaltes an chelatisierten
et de la fraction chélatée des oligo-éléments - Partie 2 : Spurennährstoffen und des chelatisierten Anteils an
Dosage de l'EDTA, du DTPA, du HEEDTA, de l'IDHA ou Spurennährstoffen - Teil 2: Bestimmung von EDTA,
de l'EDDS DTPA, HEEDTA, IDHA oder EDDS
This Technical Specification (CEN/TS) was approved by CEN on 21 February 2022 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.
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, Turkey 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
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17786-2:2022 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 Interferences . 6
6 Reagents . 6
7 Apparatus . 7
8 Sampling and sample preparation. 7
9 Procedure . 7
9.1 General . 7
9.2 Water-soluble micronutrient content . 7
9.3 Chelating agent content . 7
10 Expression of results . 8
10.1 Water-soluble micronutrient content . 8
10.2 Chelating agent content . 8
10.3 Chelated fraction (ChF) . 9
11 Test report . 9
Annex A (informative) Complete names of chelating agents . 10
Bibliography . 11
European foreword
This document (CEN/TS 17786-2:2022) has been prepared by Technical Committee CEN/TC 260
“Fertilizers and liming materials”, the secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a Standardization Request given to CEN by the European
Commission and the European Free Trade Association.
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 announce this Technical Specification: 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, Turkey
and the United Kingdom.
Introduction
Micronutrients are considered to be, in plant nutrition, a number of elements known to be needed in
small amounts for proper plant growth and development. The most common are Iron (Fe), Manganese
(Mn), Molybdenum (Mo), Copper (Cu), Zinc (Zn) and Boron (B).
If an inorganic micronutrient fertilizer contains a substance, or one of the substances in the mixture,
which is intended to enhance the long term availability to plants of micronutrients in the EU fertilizing
product, that substance is either a chelating agent or a complexing agent.
The chelating agents are divided into two groups :
— Group 1: EDTA, DTPA, HEEDTA, IDHA and [S,S]-EDDS;
— Group 2: Chelating agents present in UVCB (unknown or variable composition, complex reaction
products and biological materials) chelates including [o,o] EDDHA , [o,p] EDDHA , [o,o] EDDHMA,
HBED and EDDHSA.
This document defines the test method to be used in order to measure the compliance with the
chelated fraction of micronutrients in product function category (PFC) 1(C) (II) (classified according
to Regulation (EU) 2019/1009 [7]) as inorganic micronutrient fertilizer containing one or more
chelating agents of Group 1.
Abbreviated terms are described in Annex A.
1 Scope
This document specifies a method for the determination of the chelated fraction of micronutrients for
fertilizers containing one or many micronutrients chelated by EDTA, DTPA, HEEDTA, IDHA or [S,S]-
EDDS in fertilizers.
This method is used for inorganic micronutrient fertilizers when micronutrients are chelated only by
EDTA, DTPA, HEEDTA, IDHA or [S,S]-EDDS or for mixtures in which EDTA, DTPA, HEEDTA, IDHA or
[S,S]-EDDS is one of the chelating agents.
The method is applicable to all inorganic micronutrient fertilizers containing EDTA, DTPA, HEEDTA,
IDHA or [S,S]-EDDS as chelating agent for contents > 0,1 % (w/w).
The method is based on ICP or AAS measurement of the concentration of micronutrients according to
EN 16963 or EN 16965 after water extraction according to EN 16962 and LC measurement of the
chelating agents according to EN 15950, EN 13368-1 and EN 13368-3.
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 12944-1, Fertilizers and liming materials — Vocabulary — Part 1: General terms
EN 12944-2, Fertilizers and liming materials — Vocabulary — Part 2: Terms relating to fertilizers
EN 13368-1, Fertilizers — Determination of chelating agents in fertilizers by chromatography — Part 1:
Determination of EDTA, HEEDTA and DTPA by ion chromatography
EN 13368-3, Fertilizers — Determination of chelating agents in fertilizers by chromatography — Part 3:
Determination of [S,S]-EDDS by ion pair chromatography
EN 15950, Fertilizers — Determination of N-(1,2-dicarboxyethyl)-D,L-aspartic acid (Iminodisuccinic
acid, IDHA) using high-performance liquid chromatography (HPLC)
EN 16962, Fertilizers — Extraction of water soluble micro-nutrients in fertilizers and removal of organic
compounds from fertilizer extracts
EN 16963, Fertilizers — De
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