Analysis of nitrosamines in food

EFSA and BfR comment on health risks of nitrosamines

Aug 2023 (update). In March 2023, the European Food Safety Authority published a Scientific Opinion on the risk assessment of N-nitrosamines in food. The German Federal Institute on Risk Assessment confirmed this in its Opinion Nr. 016/2023 in April. Out of the 32 nitrosamines studied, EFSA considers 10 substances to be carcinogenic and genotoxic.

Legal background on nitrosamines

Nitrosamines belong to the most carcinogenic substances in animal experiments. Therefore, no limit values can be set below which the nitrosamines are considered harmless. The minimisation principle applies. Only for nitrosamines in malt and beer guidance values have been established (NDMA) (malt: 2.5 µg/kg; beer: 0.5 µg/kg; guideline values from Bavarian State Office for Health and Food Safety, LGL, in German).

Formation of nitrosamines in food and intake

Nitrosamines have the general chemical formula R¹R²N-NO. They are formed during the reaction of nitrite with secondary amines, which are found in many foods. One source of amines is their formation from the breakdown of amino acids during frying and stewing of foods. The addition of vitamin C and vitamin E can suppress the formation of nitrosamines, as these vitamins intercept the nitrite and thus it cannot react with the amines.

According to the EFSA Opinion, meat and meat products contribute most to the intake of nitrosamines in all age groups. In addition, nitrosamine may occur in fish, cocoa, beer and other alcoholic beverages, processed vegetables, cereals, milk and dairy products and fermented, pickled and spiced food.

Analysis of nitrosamines at Eurofins

The Competence Centre for Organic Contaminants of the Eurofins Laboratories for Food and Feed Analysis in Germany has been offering the analysis of nitrosamines by LC-MS/MS for several years. We offer the analysis of nitrosamines in different analytical scopes. The currently available nitrosamines as well as six others whose analysis is currently being implemented can be found in Table 1. These six planned nitrosamines include two parameters considered by EFSA to be of particular relevance, NMA and NSAR, so that after completion of the method extension all ten nitrosamines considered by EFSA to be of particular relevance will be part of the analytical portfolio.

Currently, the analysis is available in the matrices fish, meat, beverages (non-alcoholic and up to 5% alcohol) and malting barley/roasted malt. The validation of further matrices is already being planned.

The samples are processed according to a QuEChERS protocol by extracting the analytes using an acetonitrile-water mixture and subsequent salting. The acetonitrile phase obtained is subsequently purified using dispersive SPE. The purified extract is measured by a very selective LC-APCI-MS /MS using a special stationary reverse phase. Each of the nine analytes has its own stable-isotope-labelled internal standard for error correction.

Do you have any questions about the analysis of nitrosamines?

Please refer to your personal account manager or directly contact our expert Sindy Böhme.