Notice of Retraction Evaluation of Trace Element Levels of Some Medicinal Herbs in China

The concentrations of eight trace elements (Mg, Fe, Mn, Cu, Zn, Cr, Cd and Pb) in twelve kinds of medicinal herbs collected from China were determined by inductively coupled plasma atomic emission spectrometry after microwave digestion. Among all determined elements, magnesium was found to be the domination elemental ion as compared with other trace elements in the investigated herbs. The concentration of these trace elements were observed in the range of 525-5585, 70.5-375, 3.37-277, 0.44-14.8, 15.3-113, 0.68-8.06, 0.11-1.04, 0.25-6.48 μg·g -1 for magnesium, iron, manganese, copper, zinc, chromium, cadmium and lead. The levels of Cd in P. communic, B. chinense and C. deltoidea were found to be higher than legal limits. The accuracy and precision were verified by certified reference material, and the relative standard deviations were found below 10 %.