Leaching and bioavailability of aluminium, copper and manganese from tea (Camellia sinensis)

To assess human exposure to Al, Cu and Mn from tea drinking, eight tea samples were analysed for their ‘total’ and soluble elemental content. From this data, the percentage of ‘available’ element to the human system was calculated. Results for the samples showed that, compared to background levels for plants, concentrations of Al were highly elevated. The solubility of Al, Cu and Mn in infusions at 2, 5 and 10 min with boiling water showed that the solubility in the first infusion was the highest followed by the second and the third infusions in decreasing order. Calculation of percentage ‘available’ Al, Cu and Mn to the human system showed that tea is a rich source of dietary Mn, contributes towards our dietary copper intake, and is of no cause for concern in terms of Al toxicity in healthy individuals.