## 3 Results and Discussion
### The Content of Mineral Compounds
Cobalt (Co) is widely distributed in the body, with the highest concentrations found in the liver, kidneys, and bones. Vitamin B\({}_{12}\), found in food of animal origin, is the main source of cobalt. Considering that only 50% of vitamin B\({}_{12}\) is absorbed in the intestine, its recommended daily intake is 3 mg. Vitamin B\({}_{12}\) is necessary for the maturation of erythrocytes and the normal function of all cells [48]. Potential health risks are associated with food contamination with elements such as lead, cadmium, and nickel. The content of lead in the tested samples ranged from 0.00 mg/kg to 2.60 mg/kg, while the highest amount was found in _Equisetum arrense_ L. (Table 3). According to the Slovak regulation from September 11, 2006, the highest permissible amount of this mineral in the category \"tea for preparation the drink\" is 10 mg/kg. Thus, the lead content in all tested samples met this limit. The highest amount of cadmium was detected in _Equisetum arrense_ L., with a value of 0.43 mg/kg. According to the Slovak regulation from 11 September 2006, the maximum cadmium content in the category \"soft drinks\" is 0.05 mg/kg. In our study, mineral compounds were analyzed in dry matter, not in water extracts. No definite conclusion can thus be made regarding the amount of cadmium in aqueous solution in association with legal requirements. [PERSON] and [PERSON] [51] found that, after 5 min of extraction, 46.67% of cadmium was extracted into herbal tea samples. Prolongation of the extraction to 10 min resulted in a 53.10% extraction yield. Therefore, the extension of the extracting time caused a significant increase in the extraction yield. The authors also stated that the extraction efficiency of lead or cadmium is positively affected by acidification with lemon juice or citric acid. Cadmium (Cd) is released into the environment through natural activities (e.g., volcanic eruptions), weather conditions, and some human activities (e.g., mining, smoking, production of fertilizers, etc.). Cadmium is a highly toxic element for the kidneys, as it accumulates in  
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Sample** & \begin{tabular}{c} **Copper** \\ **(mg/kg)** \\ \end{tabular}  & \begin{tabular}{c} **Zinc** \\ **(mg/kg)** \\ \end{tabular}  & \begin{tabular}{c} **Manganese** \\ **(mg/kg)** \\ \end{tabular}  & \begin{tabular}{c} **Ion** \\ **(mg/kg)** \\ \end{tabular}  & \begin{tabular}{c} **Chrome** \\ **(mg/kg)** \\ \end{tabular}  & \begin{tabular}{c} **Nickel** \\ **(mg/kg)** \\ \end{tabular}  & \ \begin{tabular}{c} **Cobalt** \\ **(mg/kg)** \\ \end{tabular}  & \begin{tabular}{c} **Lead** \\ **(mg/kg)** \\ \end{tabular}  \\ \hline _Primula rois_  
the proximal tubular cells. Inhaling excessive amounts of this element can lead to serious lung damage. Oral intake of higher amounts of this element leads to stomach irritation, vomiting, and diarrhea. Prolonged exposure to lower concentrations can lead to cadmium deposition in the kidneys, a condition that can lead to kidney diseases, bone thinning, and lung damage [52]. According to the Slovak standard n. 608/3/2004-100 from 15 March 2004, the maximum permissible amount of nickel in the category \"legumes, nutritional supplements, snacks, honey, dehydrated and instant soups\" is 6.0 mg/kg. Among our samples, the highest nickel concentration of 3.80 mg/kg was found in _Achillea millefolium_ L. All the samples thus met the limit set by the standard for this category (Table 3). It is necessary to consider the fact that all our samples were analyzed in the form of dry matter. The extractability of specific elements into an aqueous solution will make their concentrations in the liquid lower than that observed in dry matter.