Acta Pol Pharm. 2012 Mar-Apr;69(2):279-83.
Determination of selected elements in different pharmaceutical forms of some Polish herbal medicinal products.
In the present work, the following microelements and heavy metals were determined in the Willow bark (Cortex Salicis), in the St. John's wort (Herba Hyperici), in the infusions from these raw materials and in the tablets containing these herbs: Cr, Cu, Fe, Ni, Zn and Ba, Cd, Pb. The concentration of the metals were determined by means of the GFAAS and ICP-MS methods. Considering the examined two herbs as a source of toxic metals, the occurrence of high levels (exceeding the European Pharmacopoeia limits) of Cd should be emphasized. The level of cadmium was low in the infusions because of a low extraction efficiency of this metal, so that the infusions can be found as a rather safe form of herbal medicine. In the tablets, the Cd contents were similar to the levels found in the raw materials. Because the total heavy metal content can be accessible, it may cause a potential health risk for human.