Measearment of Cadmium, Zinc, Lead, Iron, Aluminium and Copper in Imported and Internal Tea in Iranian Market by ICP-OES and ICP-MS Techniques

The amount of heavey metal elements in tea mighg have significant impact on human health. In the present study, the amount of heavy metal elements such as cadmium (Cd), lead (Pb), zinc (Zn), iron (Fe), aluminum (Al) and copper (Cu) in some imported tea samples and local tea samples cultivated in Iran have been evaluated.

The Tea samples were prepared by three different methods including Digestion, Brew and Infusion and the concentration of heavy metals in the prepared samples were measured by ICP-OES and ICP-MS.

Aluminum with a concentration of 853.9 µg/g and the cadmium element with the concentration of 0.99 µg/g were found to be the highest and lowest in the samples examind, respectively. Among the extraction methods, the concentration of extracted elements in digestion method was significantly higher than other methods. The statistical analysis of the obtained results by ICP-OES and ICP-MS revealed that there is no significant difference between the detected concentrations of Al, Zn, Fe, Cu and Cd eighter in the local or imported tea samples in each of the extraction methods. The obtained result showed that the amount of detected Pb in the ICP-MS technique for both internal and imported tea samples is significantly higher than those of ICP-OES technique.

Concentrations of all metal elements in the studied tea samples were significantly higher than of standard reference (NIESNO.7). However, the estimated daily intake of all elements for each adult person is still within the allowable level of the World Health Organization.