## 2 Results and Discussion
### Analysis and Quantification of Atropine and Scopolamine in Different Types of Infusions
As shown in Table S1, most of the tea samples were picked from organic crops (pesti-cides were not used) and probably from tea harvesting machines. When this occurs, the buds of the tea plant are harvested by cutting them together, and weeds can be accidentally cut by the machine. For this reason, leaves that do not comply with quality standards \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Infusion Code** & **Sample Description (Code)** & \
\begin{tabular}{c} **Atropine** \\ **(ng/mL \(\pm\) SD)** \\ \end{tabular} &
\begin{tabular}{c} **Scopolamine** \\ **(ng/mL \(\pm\) SD)** \\ \end{tabular} \\ \hline Herb-Inf-16 b & Mixed herbal tea (Her-16) & ND & ND \\ \hline Herb-Inf-17 b & Mixed herbal tea (Her-17) & ND & ND \\ \hline \hline \end{tabular}  
* 0.045, R 0.994).
* 0.092, R 0.999).
* \(\leq\)MQL: below or equal to the limit of quantification of the method (0.14 ng/mL for atropine and 0.18 ng/mL for scopolamine); ND: not detected.  
\end{table} 
Table 3: _Cont._  
Figure 2: Types of teas from the _Camelia sinensis_ (L.) Kuntze plant. (small tea buds, old tea shoots, etc.) and weeds should be discarded manually. From the results obtained in Table 3, it can be concluded that the cleaning process in the black tea samples is more exhaustive because black tea is a higher-quality product than green and white teas. However, assuming that the B-1, B-2, and B-3 tea samples (organic farming) were manually picked and that cross-contamination with weeds did not occur during their harvesting, the contamination observed could be due to horizontal transfer through the soil because of the existence of TA-producing plants in the vicinity of the tea fields. As can be seen in Table 3, younger parts of the _Camelia sinensis_ (L.) [PERSON] plant (first and second leaves) have a higher concentration of TAs than older parts (third leaf). These findings are in agreement with those of a study on the contamination source of toxic PAs in tea [38]. In the cited work, the authors reported that the higher concentrations of PAs found in the younger leaves of the tea plant resulted from the transference through the path of PAs producing weed-soil-fresh tea leaves in tea gardens [38]. Finally, it should be noted that the country of origin is not reported on the label of these products because Commission Regulation (EU) 1169/2011 [39] does not mandate declaring the origin of some types of food, such as teas. However, the declaration of the origin would be advisable for tea to help determine the causes of contamination by TAs. A better understanding of the occurrence, invasiveness, and preferred growing conditions of weeds that produce TAs will certainly help farmers identify the sources of tea contamination and take measures to mitigate weed contamination in the fields [3]. In the case of herbal infusion samples (Table 3), only three samples showed atropine, with two of them being below the MQL (0.06 ng/mL), Herb-Inf-4 and Herb-Inf-8. Herb-Inf-7 and Herb-Inf-8 were from fruit-flavored yerba mate (_Ilex paraquarensis_). This is the first time that atropine contamination has been reported in this type of plant. Even though its concentration was lower than the limit established by Commission Regulation (EU) 2021/1408 [29], contamination due to bad harvesting practices is unlikely. Eventually, this may be due to cross-contamination by production lines during the packaging of the product or from soil transference to the plant. Herb-Inf-9 to Herb-Inf-17 were obtained from herbal mixtures, some flavored and mixed with fruits. Atropine and scopolamine were not found in these samples, except for Herb-Inf-9 and Herb-Inf-11 infusions, which showed atropine contamination below the MQL. The contamination of Herb-Inf-9 may originate from linden, which has been previously reported to have high TA concentrations [30]. In the case of Herb-Inf-11, contamination may come from _Cymbopogon citratatus_, although it would also be interesting to investigate the presence of atropine and scopolamine in hibiscus.