Atropine and scopolamine occurrence in spices and fennel infusions

Abstract

Tropane alkaloids (TAs) are toxic anticholinergic compounds that appear due to accidental contamination of foods with TA-producing plants. Atropine and scopolamine are the most common TAs and their maximum levels in certain foodstuffs have been recently regulated, including food supplements. TAs occurrence in commercial products and the transfer ratio to herbal infusions prepared from contaminated spices are of interest for exposure assessment of consumers. In this study, the occurrence of atropine and scopolamine was investigated in a total of 51 commercial spices of 6 types (ginger, cloves, fennel, cumin, aniseed, coriander) and a mix of spices and herbs (curry) purchased in Portugal (19 samples) and Spain (32 samples) in 2021. Results evidenced that more than half of the samples analysed (67%) were contaminated with one or both analytes. Fennel, cloves and coriander showed the highest concentrations ranging between 5-31 μg/kg, 8–28 μg/kg and 5–45 μg/kg, respectively, for the sum of atropine and scopolamine. On the other hand, the transfer ratio of the target analytes found in four naturally contaminated fennel samples was studied. Infusions were prepared according to International Standard ISO 3103 protocol, and a transfer ratio between 64 and 88% for atropine and between 47 and 57% for scopolamine was found.