Assessment of heavy metals in infused tea marketed in Riyadh, Saudi Arabia, using inductively coupled plasma-mass spectrometry: human health risk assessment

The present study aims to investigate the levels of some heavy metals: Arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) in infused tea consumed in Riyadh, Saudi Arabia, and their potential health risk. Inductively coupled plasma mass spectrometry (ICP-MS) was used to assay the concentration of heavy metals in tea samples, after microwave acid digestion. This study was carried out on 25 brands of tea purchased from Riyadh city supermarkets. The validation of the proposed method was developed by measuring different parameters e.g. accuracy, precision, linearity, the lower limit of quantification (LLOQ), the lower limit of detection (LLOD). The method was examined for the determination of As, Cd, Pb and Hg in spiking samples with good accuracy and precision. The average daily intake (ADI), the hazard quotient (HQ), the total hazard quotations (THQs), and hazard index (HI) of the investigated metals were used for the assessment of health risks associated with the intake of metals. The mean concentration of heavy metals in infused tea were found in the range of 0.008-0.445, 0.0097-0.044, 0.012-2.379 and 0.0053-0.044 mg/kg for As, Cd, Pb and Hg, respectively. The results revealed that the concentration of As, Cd and Hg metals in all samples of infused tea was considered in the standard range, whereas the concentration of Pb exceeded the maximum concentration limit presented by World Health Organization (WHO). Therefore, the continuous monitoring of the concentration of heavy metals in tea is essential on a regular basis.