Tropane alkaloid contamination of gluten-free cereal food

Cereal crops are susceptible to contamination with tropane alkaloids from the seeds of certain weeds growing in the same fields. The low gluten content of crops like corn, rice, buckwheat, and millet makes them essential ingredients in gluten-free foods, which serve as nutritional therapy for people with a gluten intolerance or celiac disease. The current study aimed to address the lack of data on the presence of the main tropane alkaloids, atropine and scopolamine, in such foods.

The atropine and scopolamine content of 71 prepacked gluten-free cereal foods collected on the Serbian market were determined by liquid chromatography with tandem mass spectrometry (LC-MS/MS; limit of quantification of 0.4 μg/kg for each analyte) and further used for regulatory compliance assessment (maximum level for millet, sorghum, and maize products: 5 μg/kg; maximum level for buckwheat: 10 μg/kg).

Overall, atropine was found in 42.3% of the samples and scopolamine in 35.2%. Regarding the contamination frequency, the distribution across the food groups was as follows: flour (66.7%) > biscuits (53.3%) > pasta (41.7%) > crackers (35.0%) > bread (25.0%) > breakfast cereals (0%). The total concentrations of atropine and scopolamine varied widely among the food groups, with a maximum of 60.8 μg/kg in flour and 32.4 μg/kg in pasta. Notably, two flour samples (16.7%; made from corn/corn, rice, and millet) and one pasta sample (8.3%; made from corn and rice) exceeded the permissible limit. The overall mean ratio of atropine to scopolamine in the same pasta sample was 2.4 ± 1.1, suggesting contamination with Datura stramonium seeds.

The recorded non-compliance rate of 4.2% in the gluten-free food samples, with contamination greatly exceeding the regulatory limit, is of public health importance. Although processing of samples such as flour and pasta can modify the composition and concentration of tropane alkaloids in ready-to-eat food, solid information on the degree of degradability and toxicity of the products formed is still unavailable.