Herbs and spices are commonly used in cuisine all over the world. They may contain many various substances beneficial for health, but also harmful (e.g. metallic) elements. Spices and herbal plants contain metal ions over a wide range of concentrations. Metals can have important positive or negative roles in human life.
The aim of this study was to estimate the trace metals content in select popular Polish herbs and spices available on the Polish market. Thirty samples of various herbs and spices (fennel, sage, oak bark, St. John's wort, linden inflorescence, mint, black pepper, garlic, marjoram, paprika, cinnamon, basil, oregano, herbs de Provence, and parsley) were analyzed. The contents of Cu, Ni, Fe, Zn, and Mn were determined using AAS method after sample mineralization with 65% nitric acid and 30% hydrogen peroxide. Metals contents were compared in spices from different manufacturers. The chemometric techniques were used to evaluate similarity with respect to herb and spice metal contents.