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. 2023 Apr 28;28(9):3802.
doi: 10.3390/molecules28093802.

Essential and Potentially Toxic Elements (PTEs) Content in European Tea (Camellia sinensis) Leaves: Risk Assessment for Consumers

Federico Girolametti  1 , Anna Annibaldi  1 , Silvia Illuminati  1 , Elisabetta Damiani  1 , Patricia Carloni  2 , Cristina Truzzi  1
Affiliations

Essential and Potentially Toxic Elements (PTEs) Content in European Tea (Camellia sinensis) Leaves: Risk Assessment for Consumers

Federico Girolametti et al. Molecules. .

Abstract

Tea (Camellia sinensis) is the second most consumed beverage worldwide, playing a key role in the human diet. Tea is considered a healthy drink, as its consumption has been linked to a lower risk of cardiovascular disease-related events and death, stroke, metabolic syndrome and obesity. However, several studies have shown that C. sinensis is a hyperaccumulator of Al and other elements that are considered potentially toxic. In the present study, the contents of 15 elements (both essential and toxic) were determined for the first time in tea leaves collected in tea gardens located in six different European countries and processed to provide black and green tea. The results showed that Al was the major toxic element detected, followed by Ni, Cr, Pb, As, Cd, Ag, and Hg. Essential elements were detected in the order of Mn, Fe, Zn, Cu, Co, and Se. Statistically significant correlations (p < 0.05) were found in the distribution of some elements, highlighting mechanisms of synergic or antagonist interaction. Multivariate analysis revealed that geographical origin was the main driver in clustering the samples, while the different treatment processes (black or green) did not significantly affect the contents of elements in the leaves. The estimation of potential non-carcinogenic risk revealed no risk for the consumption of European teas for consumers in terms of potentially toxic elements.

Keywords: C. sinensis; Europe; essential elements; food quality; food security; leaves; potentially toxic elements (PTEs); risk assessment; tea.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Essential (a) and potentially toxic (b) element contents in European tea leaves.
Figure 2
Figure 2
Comparison between element contents in the black and green European tea leaves. Different letters within the same plot indicate statistically significant differences in element contents between the two different types of tea (p < 0.05).
Figure 3
Figure 3
2D biplot of PC1 vs. PC2. B: black tea; G: green tea; CH: Switzerland; PT: Portugal; NL: the Netherlands; IT: Italy; UK: the United Kingdom; KR: the Republic of Korea; VN: Vietnam; AZ: Azores.
Figure 4
Figure 4
Correlogram plot on element content in European tea leaves. * denotes a statistically significant correlation (p < 0.05).
Figure 5
Figure 5
Location of European gardens where tea samples were collected. CH: Switzerland; PT: Portugal; NL: the Netherlands; IT: Italy; UK: the United Kingdom; DE: Germany.
See this image and copyright information in PMC

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