Original research articleDetermination of metalloid, metallic and mineral elements in herbal teas. Risk assessment for the consumers

- As, Cd, Cr, Cu, Hg, Fe, Pb, Mn, and Zn were analyzed in herbal teas.
- Samples were obtained from supermarkets, street herbal markets and herbal stores.
- Cd levels in some thyme and chamomile samples exceeded maximum permissible limits.
- Solubilization in herbal infusion and bioavailability of elements was considered.
- Overall, exposure to metallic elements in herbal teas do not pose health risks.

In spite of herbal teas having potential health benefits, the presence of metal contamination in these products has raised public health concerns. An analytical method for the determination of metallic elements (Hg, Pb, Cr and Cd), metalloids (As) and mineral compounds (Fe, Mn, Cu, and Zn) in herbal teas has been validated. Levels of these elements were determined in 220 samples of herbal teas purchased from supermarkets (which marketed own and leading brands), street herbal markets and herbal stores. In a further step, potential human health risks for the consumers were assessed. Cd in thyme and chamomile from some selling points exceeded the maximum permissible limit set by the WHO and the European Pharmacopoeia for herbal medicines or herbal drugs (also referred to as herbal teas). Regarding mineral elements, the highest Mn levels were found in red and green tea among all plant studied, in line with other studies. However, the estimated daily intake of metal/metalloid and mineral elements from the commercial herbal teas studied, considering the percentage of solubilization in infusions and the bioavailability of each compound, do not pose human health risks.