Authors:Hai-Qing Zhang, Bang-Fa Ni, Wei-Zhi Tian, Gui-Ying Zhang, Dong-Hui Huang, Cun-Xiong Liu, Cai-Jin Xiao, Hong-Chao Sun and Chang-Jun Zhao
Twenty different brands of Chinese tea were analyzed for multiple trace elements, including some essential and toxic elements,
by neutron activation analysis (NAA). A comparison among tea brands from China, India, US and other countries was made for
the ranges and averages of concentrations for Na, K, Mn, Cu, and Br. It has been observed that the trace element contents
in tea leaves are largely dependent upon the soil and the environment where the tea grows. Chinese tea is rich in Mn and Cu
comparing with those of other counties surveyed, but is indigent in Na. The transference ratio for each element determined
(i.e., the fraction of an element in tea leave transferred into solution when tea is leached by percolation) is also reported.
Adult daily intakes of some essential and toxic elements from tea drinking were also estimated.