Reference Laboratory for Process Contaminants in Foodstuffs

Process contaminants can arise during the processing of food and pose health risks. As the National Reference Laboratory for Process Contaminants in Foodstuffs, METAS provides technical support to the official food inspection authority (cantonal laboratories) and the central federal authority (Federal Food Safety and Veterinary Office).

© METAS

Why are process contaminants in food examined?

Process contaminants are toxic compounds that can form as undesirable by-products during the processing of food. These are formed, for example, during fermentation, smoking, drying, refining or heating at high temperatures.

Known process contaminants include:

• Polycyclic aromatic hydrocarbons (PAHs)
• Free 2- and 3-monochloropropanediols (MCPDs) esterified with various fatty acids
• Glycidyl fatty acid esters (GE)
• Acrylamide
• Furan and alkylfuran

As these process contaminants sometimes have carcinogenic, mutagenic or organ-damaging properties, maximum levels in food have been defined to protect consumers. These are set out in the Contaminants Ordinance:

• FDHA Ordinance on the Maximum Levels for Contaminants (Contaminants Ordinance, ContO, SR 817.022.15)

Reliable analyses to determine the content of process contaminants are essential for food safety. To ensure this, the Federal Food Safety and Veterinary Office (FSVO) has appointed METAS as the National Reference Laboratory (NRL) for Process Contaminants in Foodstuffs.

Detection methods and analysis methods

At METAS, we maintain a portfolio of analyses in the trace range for process contaminants.

We perform the analysis mainly using gas and liquid chromatography coupled with mass spectrometry.

In the document “List of analytical methods for processing contaminants in food” you will find information on available standard analytical methods and certified reference materials.

• List of analytical methods for processing contaminants in food

  PDF125.76 kB15 October 2026

Quality

Accreditation

As a National Reference Laboratory, we are accredited in accordance with the European standard EN ISO/IEC 17025 “General requirements for the competence of testing and calibration laboratories” (accreditation number: STS 0119).

• Accredited scope of the METAS test laboratory STS 0119

Validation of methods and suitability tests

In order to ensure that the quality of our analyses remains at the highest level, we are taking part in the validation of methods studies and in the suitability tests organised by the European Union Reference Laboratory.

If required, we also organise or arrange aptitude tests for the cantonal laboratories.

National and international cooperation

As the National Reference Laboratory, we represent Switzerland at meetings and in working groups organised by the European network. The aim of this collaboration is to:

• promote the exchange of knowledge
• forward the recommendations of the European Union Reference Laboratories to the national bodies

In order to pass on important findings and developments from the international meetings to Swiss circles of experts and to promote dialogue with the cantonal enforcement laboratories, we organise a national symposium every year.

NRL Symposium on the Analysis of Process Contaminants

The next symposium of the National Reference Laboratory for Process Contaminants will take place on 12 November 2026 at the Liebefeld Campus.

For further information on the symposium, please contact: [e-mail]

More information

• European Union Reference Laboratory (EURL) for Processing Contaminants

• Legal basis

  • FDHA Ordinance on the Maximum Levels for Contaminants (Contaminants Ordinance, ContO, SR 817.022.15)
  • Ordinance on Foodstuffs and Consumer Products (FCPO, SR 817.02), Art. 31 (requirement of approval)
  • Ordinance on Foodstuffs and Consumer Products (FCPO, SR 817.02), Art. 32 (tolerances)