عنوان مقاله English
Tea is one of the most popular drinks in the world and because of its health benefits to human it has got considered as a medicinal plant. Tea plant (Camellia sinensis) can uptake metal elements particularly Aluminum and accumulate them on different parts of the plant. There are reports on the relation of the heavy metals Arsenic and Aluminum with disease like Alzheimer's. Because of the high consumption of tea in our country and the adverse effects of the elements like Al, Cd, Sr, Pb, Ni and Co on human health, the aim of this study was the determination of these elements in tea. Four groups of Tea samples (Iranian tea, imported tea, mix tea and tea bags (four samples for each group) were selected randomly and purchased from local supermarkets (Sharvand or Refah) in Tehran. Samples prepared by wet ashing method by the application of concentrated chloric acid & nitric acid, then the elements were determined in Inductively Coupled Plasma-Optical Emission Spectrophotometer (ICP-OES). All the tests were done on duplicate basis. For the evaluation of statistical parameters, mean and standard deviation, non-parametric test (Kruskal-wallis) and both one way and two way variance analysis were applied. For evaluation of the data the SPSS version 13 software was used. Results showed that the amount of elements Pb, Co, As and Cd in all tea samples were lower than instrument detection limit (0.14, 0.05 and 0.015 ppm, respectively). There were significant differences in total amount of Al in between tea groups (p<0.05). For Ni there were no significant differences in between tea groups. In the case of Sr there were significant differences only in imported tea groups with the others, but also there were significant differences in the samples of each group (p<0.05). This study indicated that the levels of the elements in most Iranian tea samples were higher than other tea types. In order to solve the tea production and processing problems more researches should be done on these areas.
کلیدواژهها English
