Inversion-voltamperometric determination of heavy metals in medicinal plant samples

Abstract

Increasing interest in the use of medicinal plants or their mixtures (herbal teas) in the prevention and treatment of diseases requires confirmation of the safety of the plants used. The reason is the heavy metals they contain can enter the human body together with the useful substances. The purpose of this paper is to determine the content of some heavy metals in medicinal plants produced by AltaiVita, Barnaul, Russia; KIMA, Barnaul, Russia, and PharmaCvet, Moscow, Russia by inversion voltammetry. The content of heavy metals we determined in 10 samples of medicinal plants from producer "AltaiVita". We preliminarily determined the moisture content of the examined raw material. The Cd content was 0.16-0.50 µg/kg, Pb - 0.33-0.85 µg/kg, Zn - 0.010-0.043 µg/kg, Cu - 10.1-55.9 mg/kg, that does not exceed maximum allowable content by standards of State Pharmacopoeia for medical plants and SanPiN 2.3.2.1078-01 for dietary supplements ("dried tea"). According to the standard content in plants (normal, average and toxic content of copper) exceeded in almost all samples (except for Cinquefoil white). We compared the content of heavy metals in samples of medicinal plants from AltaiVita, KIMA, and PharmaCvet. The content of Cd, Pb, Zn in KIMA and PharmaCvet samples was an order of magnitude or higher than the content of these metals in AltaiVita sam-ples; the content of Cu in AltaiVita samples was comparable or 2 times lower than in KIMA and PharmaCvet ones.