[Determination of heavy metals in samples of herbal drugs using differential pulse polarography].

The contamination of the environment requires the content of heavy metals in medicinal plants to be limited and controlled. The present paper aims to demonstrate the possibilities of application and advantages of a modern polarographic method, differential pulse chromatography (DPP), in the identification and determination of heavy metals in the plant material. In the plant drugs Flos chamomillae and Flos calendulae, the heavy metals Pb, Cd, Ni, Zn, Cu and Fe were identified and determined. The World Health Organization (WHO) indicated Pb, Cd and Ni as dangerous toxic trace elements.