Determination of metal content in some herbal drugs—Empirical and chemometric approach

The concentrations of Cu, Zn, Mn, Fe, K, Ca, Mg, Al, Ba and B in 26 herbal drugs of special importance in phytopharmacy were studied. Flame atomic absorption and emission spectrometry (FAAS, FAES), as well as inductively coupled plasma atomic emission spectrometry (ICP-AES), were applied in this work. The whole procedure, from sample preparation, via dissolution, to measurements, was validated by using CRM (NIST 1573a—tomato leaves), and the obtained recovery values are in the range from 91 to 102%. Drug samples originated from medicinal plants cultivated in Serbia contained Cu (4.47–14.08 mg kg−1), Zn (8.4–54.5 mg kg−1), Mn (9–155 mg kg−1), Fe (47–546 mg kg−1), K (0.20–6.24%), Ca (0.18–1.84%), Mg (0.13–1.09%), Al (16–416 mg kg−1), Ba (11.70–84.83 mg kg−1) and B (5.1–118.7 mg kg−1). In order to get a better insight into the elemental patterns, a common chemometric approach to data evaluation was used. Four significant factors identified by principal component analysis (PCA) were attributed partly to the significant influential sources and high mobility of some elements thus referring to potential anthropogenic contamination as well.