Application of hyphenated plasma mass spectrometry to the study of elevated metal toxins in brewed beverages

Hyphenated plasma mass spectrometry is a powerful tool for ultra-sensitive measurements in aqueous solutions. Our team investigated elevated levels of aluminium, manganese, nickel and chromium in brewed beverage samples (tea). Tea is a popular beverage and is consumed on a regular basis by adults and children. Elevated concentrations of toxins could be detrimental to the human body and remediation measures are necessary to reduce the levels of these metal toxins in tea leaves. Eight brands of tea samples were analysed for toxic trace metals after brewing in ultrapure Millipore water. A study of this nature, where metal toxins are extracted by boiling, is relatively underexplored. High resolution Inductively Coupled Plasma Mass Spectrometer was employed to examine the levels of the elements of interest. The performance of the instrument was validated using certified reference standards. Minor perturbations in performance were adjusted by use of an internal standard. The selected elements produce elevated levels in excess of a factor of 20 in some cases, compared to European Union standards for drinking water. These toxins tend to originate from the soil and water used to cultivate the tea leaves, and possibly from the chemical processes linked to the production of the tea leaves. It may be possible to use these elevated elemental levels to identify or “fingerprint” the country of origin of the corresponding tea sample. Our work could be considered a valuable source of reference data, and could contribute to sustainable development.