Scope & Background
The updated Swiss Ordinance 817.023.21 (Revision February 1st 2024, AS 2023 836 ff.) will enter into force on February 1, 2026. The new article 35a requires at all marketing stages, except for retail sales, a Declaration of Compliance (DoC) for printing ink layers as a component of a consumer product, for printing inks, and for the materials used in the manufacture of printing inks. The Declaration of Compliance must be issued by a responsible person and contain the information specified in Annex 15 of 817.023.21. Link

This guideline aims to support the legal requirements by giving advice how all stakeholders could fulfil the set-out criteria, especially of Annex 15 of 817.023.21. It is not a legal advice nor legally binding but the outcome of exchanges in the value chain. This is especially valid for the DoC template in the annex.

To harmonise the information-flow, a standardized SoC – information from ink supplier to converter – and a standardized DoC – information from converter to food industry – is needed [1]. In this, the revision of the SIO does not impose fundamental changes in the responsibilities within the supply chain. Printing ink manufacturers cannot take (legal) responsibility for processes they do not control. An SoC is part of the compliance work needed for issuing a DoC on the next stage of the value chain. However, the suppliers’ DoCs belong to the ‘supporting documents’ (documents in accordance with Art. 35b). [10]

This SoC guidance in the annex was developed by a working group of the Swiss Packaging Institute (SVI), including the FSVO and industry representatives, to avoid any misinterpretations of the legislation based on examples. The backbone of the current template is the FAQ document, published on the web page of Swiss Federal Food Safety and Veterinary Office (FSVO/BLV) [2]. A SoC or a DoC can never cover all possible usage cases. Therefore, the proposals are always linked to defined application conditions in terms of surface-to-volume ratio, printing film weight, ink coverage amount, etc, which are under control of the converter.
Concepts and examples for calculations are provided with this guideline.

Substance definitions:
The Swiss ordinance is based on a positive list allowing a differentiation:
1) IAS: Intentionally added substances
    This group can be separated into:
    a. Listed substances (LS): meaning substances which are intentionally added to the ink formulation and listed either in Annex 2
        (equivalent to Regulation (EU) 10/2011) or 10 of the Swiss Regulation
    b. Non-Listed substances (NLS): meaning substances which are part of the ink formulation but not listed in Annex 2 or 10 of the Swiss Regulation.

2) NIAS: non-intentionally added substances
meaning substances which may occur as contaminations of the raw materials used or degradation or reaction products when processing the ink.
Raw material mixtures may also contain impurities, residual starting substances etc., which are NIAS. This definition is based on the EUPIA NIAS definition [2].

Risk assessments can be performed according to the guidance and opinions issued by EFSA, depending on the extent of available toxicity data. NIAS classified and/or known as being genotoxic and/or non-threshold carcinogens (CM-substances) or should not migrate above 0.15 µg/kg food. For reprotoxic substances (R) and threshold-carcinogens (C), higher threshold values can typically be derived through a toxicological risk assessment.

3) CMR: carcinogenic, mutagenic, toxic for reproduction
A CMR substance is not allowed to be intentionally used as NLS. If a CMR is a NIAS, it needs to be risk-assessed (see above 2).

Trade Secrets
It may happen, that certain substances are not disclosed due to trade reasons. This can be accepted if further information is given in terms of substance classification (e.g. CMR, IAS, NLS, NIAS) and an action is defined. If delegation to converter is foreseen, the way of disclosure and to whom should be described.

CMR Assessment of NLS
For CMR assessment two possibilities have to be differentiated
  1) Check the harmonized classification of the substance according to ChemV. However, the CMR info in a Safety Data Sheet according to the
      GCL of  CLP starts only from a concentration > 0.1 % (for CM) and >0.3 % (for R) – this might conflict with the limit based on the calculation
      model and might not be sufficient for the assessment.
2) no harmonized classification for the substance exists.
    At first check available toxicological data, if no data is available, then:
     a. Clarify the endpoint “M” via read-across and/ or in silico (with suitable SAR or QSAR models).
b. Clarify the endpoint “C” by read across or literature research (“expert judgement”), where possible, while for threshold carcinogens the limit
    of 10 µg/kg food can be accepted for NIAS
c. Clarify the endpoint “R” by calculating a threshold, where possible.
    If no tox-based threshold can be achieved, the limit of 10 µg/kg food can be accepted for NIAS. (see pragmatic assessment approach
    in the latest EuPIA document [4])

Expert Judgement – As Key Legal Criteria for Experts the following could be used:
   i. Qualification: Demonstrated expertise in a relevant field
   ii. Relevance: Their opinion must relate directly to the issue in question
   iii. Reliability: Based on accepted scientific or technical principles

DoC of Converter
In the best case: the information received from the ink supplier, in the proposed SoC/DoC format – to the extent applicable for the ink supplier – already estimates the compliance for many substances. Nevertheless, compliance for these substances must be verified at the converter stage. Additionally, it is the obligation of the converter to check if the applied model calculations, assumptions, and testing approaches are applicable for the final application. Converters must verify the compliance for substances, for which the information received via the SOC from the printing ink manufacturer is not sufficient/100% applicable (e.g. WCC of ink supplier needs recalculation on real case; migration test necessary) or for substances which may also occur from other sources of the final printed material. The compliance verification can be based, as mentioned, on further worst-case calculations, modelling principles, and/or migration testing.
A similar template format could be used for this purpose, but this is not subject to this current guidance document. NIAS formed during the converting step (including printing) must be assessed for the final printed food contact material.

General Considerations for the assessment of the printed article compliance
(specifically to be considered by testing laboratories, converters and brand owners)
The following general considerations give some ideas to the converters how to act in case NIAS results are questionable. The considerations are not conclusive but offer a guidance.

NIAS Assessment
For the assessment of NIAS in a printed article, the EFSA Note for Guidance (2008) and the subsequent EFSA publications on this topic are decisive for the FSVO. [3]
Important to note: NIAS from a printed article may come as result of e.g. degradation, contamination or impurities from any of the packaging components (substrate, adhesives, primers, inks, etc) or from the printing process.
So, what happens if a NIAS cannot be identified – the so-called “unknowns” in analytical reports? In this case it is worthwhile to do the following:
  a) Repeat the analysis to find out if the finding is systematic. In case of random findings, it might be impossible to run a root cause, or
  b) Revise the test conditions – selecting a more appropriate simulant instead of running a worst-case scenario, or
  c) Try to collect NIAS out of migration simulants (which is a rather scientific approach and may not be applicable in a day-to-day business).
  d) Change the packaging system, e.g. include a barrier.

Migration Tests
For migration tests, especially for non-plastic applications like paper and board no harmonised conditions are set out in relevant food contact legislation addressing especially potential migrants from print layers. This may lead to many discussions in case of findings that are exceeding limits. In that case it is highly recommended to discuss upfront, what might be relevant testing conditions. Just simply applying conditions taken from Regulation (EU) 10/2011 for plastics to non-plastics should be avoided – see also EUPIA Testing guideline [5]

Generally, it is worthwhile to verify migration test results exceeding a limit as follows:
When failing in migration tests (result > SML or for NLS >0.01 mg/kg), it is possible albeit expensive to perform tests in real food applications as the simulants might be overestimating (see also Regulation (EU) 10/2011, article 18/6). This advice may be given in the SoC, if suitable conditions are known.

The alternative to food testing is to implement a suitable barrier. However, the effectiveness of a barrier itself needs to be demonstrated on the final printed article (this is responsibility of the Business Operator as defined in Reg. 1935/2004). If known, the printing material supplier may provide data regarding which barrier material may be suitable, e.g. material type, thickness, time/temperature conditions, etc.