The aim of the study was to assess the occurrence and concentrations of TAs in cereal-based products from retail stores across different regions in Europe.
A total of 1,709 samples of plant-derived food products, mainly produced in Europe, were analysed for tropane alkaloids.
The samples, of which 27.4% came from organic production, were collected from retail stores, between June 2015 and August 2016 in Czech Republic, France, Germany, Hungary, Italy, the Netherlands, Poland, Spain and the UK.
RIKILT collected samples from the Netherlands and Germany; IRTA did this for Spain, France and Italy; UCT from the Czech Republic, Poland and Hungary and FERA within the UK.
All samples were analysed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS).
Scarce knowledge
EFSA’s panel on contaminants in the food chain (CONTAM) assessed the risk for public and animal health related to tropane alkaloids in food and feed in 2013.
Knowledge on toxic effects of TAs, other than atropine and scopolamine, are scarce, said the report.
“This means that at this moment all TAs are considered toxic and it is advised to measure all TAs for which an analytical standard is available,” it added.
Food containing co-occurring TAs associated with intoxications in the EU has been reported in tea contaminated with Atropa belladonna; buckwheat/millet bread/flour with Datura; leafy vegetables from the wild containing/composed of Datura or Mandragora officinarium and vegetables canned/frozen with Datura.
Tropane alkoloids
Tropane alkaloids (TAs) are secondary metabolites produced by a wide variety of plants. The group of TAs comprises more than 200 compounds. Atropine and scopolamine, the best known, are strong antimuscarinic agents. Toxic effects of other TAs and calystegines are largely unknown. Some crops such as potatoes and aubergine, are known to produce TAs while other food crops can be contaminated when TA containing weeds are co-harvested with the crop.
The report also mentioned changing consumption habits with Buckwheat being an example of a gluten free product, replacing wheat items. It is more often contaminated with TAs from co-occurring weeds. If consumption of these foods increases, the TA exposure could increase significantly for EU citizens.
Samples analysed for 24 TAs were 268 single component flours (buckwheat, millet, corn), 260 cereal-based foods for young children age 6-36 months (breakfast cereals, biscuits and other cereal-based foods), 219 breakfast cereals, 164 biscuits and pastry, 114 bread, 81 pasta, 121 dry (herbal) teas, 78 legumes and stir-fry mixes.
The typical patterns of TAs differed between the food product groups, according to the report.
“In single flours and cereal-based products that did not contain vegetables, the Datura-type TAs atropine and scopolamine were the major components.
“Mixed vegetable products and ready-to-eat meals for children containing vegetables as ingredients often contained the low molecular weight TAs tropine and pseudotropine as the major TAs.
“The herbal teas contained TAs from all types, most notably convolvine, atropine, scopolamine, tropine and pseudotropine.”
Samples analysed for six calystegines comprised 308 potato, 90 aubergine and six bell peppers.
Results of detection
One or more TAs were detected in 21.3% of single component flours, 20% of cereal-based foods for young children age 6-36 months, 6.8% of breakfast cereals, 14.6% of biscuits and pastry, 15.8% of bread, 70.2% of dry (herbal) tea, 26.2% of legumes and stir-fry mixes, 100% of potatoes and 92.7% of aubergines. None were detected in pasta.
The highest mean TA concentration was in cereal-based meals for children (130.7 μg/kg), and the maximum concentration was in a dry herbal tea sample (4357.6 μg/kg).
Atropine and scopolamine were most frequently detected with a maximum sum concentration of 428.5 μg/kg in a dry herbal tea.
Atropine was detected most often above the limit of detection (226 times), followed by scopolamine (172), pseudotropine (70) and tropine (54).
TAs not detected included acetylscopolamine, anisodine, homatropine, a-hydroxymethylatropine and phenylacetoxytropane, while littorine, scopine and scopoline were reported only once.
For just over half of the samples (51.6%) no country of origin was indicated. For 474 samples (36%) a single country of origin was indicated, of these the UK was the top producer (8.7%).
A total of 97 (7.4%) came from outside the EU. A large part was single component flours (buckwheat and millet) produced in China, Ukraine or the US.
EU regulation action
Commission Regulation (EU) 2016/239 set a maximum level (ML) for presence of tropane alkaloids in certain cereal-based foods for infants and young children.
The regulation mentions those foods containing millet, sorghum, buckwheat or their derived products. The ML is set at 1 μg/kg for atropine and 1 μg/kg for scopolamine. An ML for the sum of atropine and scopolamine is not given.
Of the eight samples, six exceeded the limit for either atropine or scopolamine.
Three samples that contained the highest amounts were collected in 2015 before starting date of the regulation.
The three others were collected in March 2016, just after the starting date. Although these exceeded the ML for atropine, the sum of atropine and scopolamine was below 2 μg/kg.