Tropane alkaloid-associated health risks in people on gluten-free diet

Gluten-free food, a nutritional therapy for people with a gluten intolerance/celiac disease, is produced from crops (corn, rice, buckwheat and millet) which are highly prone to contamination with the seeds of plants producing tropane alkaloids. The current study was undertaken to determine the health risks associated with atropine and scopolamine, the toxicologically most important tropane alkaloids.

A total of 71 cereal foods labelled as gluten-free were collected on the Serbian market. Atropine and scopolamine were quantified using liquid chromatography with tandem mass spectrometry. For the purpose of consumer health risk assessment, the upper-bound concentrations were considered alongside national acute food consumption data, and the resulting acute exposure was compared with the group acute reference dose (ARfD) of 16 ng/kg bw, as well as the clinically significant minimal acute dose (1.54 µg/kg bw; for calculation of the margin of exposure (MOE)).

The exposure to the combination of atropine and scopolamine exceeded the group ARfD in the case of two flour samples and one pasta sample when they were consumed by toddlers and children, one flour and one pasta sample when they were consumed by adolescents and adults, and one pasta sample when they were consumed by pregnant and lactating women and vegetarians. In cases of high food consumption, in addition to two flour samples and one pasta sample posing a risk of acute adverse effects in all the population groups, bread and biscuit samples exceeding 50% of the group ARfD in the case of consumption by toddlers (2+2) and children (1+1) also attracted attention. Regarding the MOE results, the lowest MOE of 9 was observed for one pasta sample if it was consumed in high amounts by toddlers, rising to 22 in cases of mean food consumption, which can be considered sufficiently protective.

Adverse acute health effects of tropane alkaloids cannot be ruled out even in the case of single-source dietary exposure, while aggregate exposure from multiple food sources consumed in the relevant time-frame increases concerns.