Determination of Nine Trace Elements in Tea Standard Reference Materials

An isotope dilution spark source mass spectrometric method (ID—SSMS) has been developed for the certification of nine trace elements (Th, Pb, La, Ce, Cu, Zn, Rb, Sr, Ba) in home tea and tea leaves reference materials. The method of ashing, spectral interferences and selection of the interference-free lines and the optimum spike addition have been studied. The radio isotope ~(230)Th is applied as spike of Th. The determined concentrations are in good agreement with the certified values and the accuracy has been improved by this procedure.