By chemical elements we primarily mean metals. Some are essential trace elements, others can be poisonous even in small quantities. They can be stored by plants, animal feed and fish from the environment and enter foodstuffs accidentally. They can also be absorbed in the processing of foodstuffs, for example, through unsuitable crockery. Threshold values have been defined for chemical elements in foodstuffs, as they can have a negative impact on health (poisoning or causing illnesses).
Nitrogen compounds include nitrate, which is a component of fertilisers or soil and which is absorbed by the roots of plants. Nitrate is relatively harmless to health. However, nitrate can be converted into nitrite in foodstuffs or through digestion by enzymes. Together with amines, nitrite can form nitrosamines which are carcinogens. Nitrites (E249-250) and nitrates (E251-252) are also used to preserve foodstuffs such as cured meat products and fish. Due to a possible negative impact on health, threshold values for nitrate and nitrite in foodstuffs have been defined.
Accordingly, we are dependent on a precise analysis of chemical elements and nitrogen compounds.
In the National Reference Laboratory for Chemical Elements and Nitrogen Compounds in Foodstuffs, we perform this analysis on behalf of the Federal Food Safety and Veterinary Office (FSVO) mainly using mass spectrometry with inductively coupled plasma (ICP-MS) for elements and ion chromatography (IC) for nitrate/nitrite.
Validation of methods and suitability tests
In order to continue to offer our analyses at the highest level, we are taking part in the validation of methods studies organised by the EU reference laboratory and in the suitability tests organised by the EU reference laboratory.
If required, we will organise and mediate suitability tests for the cantonal laboratories.
As the National Reference Laboratory for Chemical Elements and Nitrogen Compounds in Foodstuffs, we represent Switzerland in the meetings and working groups organised by the European network. The goal of this cooperation is to promote exchange, to pass on the recommendations of the EU reference laboratories and to receive the feedback from the cantonal laboratories entrusted with the official controls.
We organise annual knowledge sharing conferences on the analysis of chemical elements and nitrogen compounds in foodstuffs.
The NRL conference will take place on 1 December 2022. Please contact NRL-MN@metas.ch for more information.
Federal Institute of Metrology
Reference Laboratory for Chemical Elements and Nitrogen Compounds in Foodstuffs
Last modification 17.10.2022