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A total of 30 tea samples of different origins, thirteen green tea samples, thirteen black tea samples, two semi-fermented tea samples and one white tea, imported to the Czech Republic, were collected and analysed for the total content of copper, iron, manganese, and zinc in tea leaves and tea infusions. The total contents of metals in tea leaves differ according to the type of tea (green or black) and are probably influenced by many other factors, e.g. soil properties. The total contents of Mn were much higher compared to the total contents of Cu, Fe, and Zn, and varied between 511–2220 mg/kg. To compare easily hot water soluble concentrations of Cu, Fe, Mn and Zn, 5 min, 60 min, and 24 h infusions were prepared. The extractability of the elements was in the order Cu > Zn > Mn > Fe. The proportions of the element contents in the infusion related to the respective total contents in leaves were 30 ± 16% Cu, 26 ± 10% Zn, 18 ± 10% Mn, and 1.5 ± 0.8% Fe, respectively. The results confirmed that tea infusion can be an important dietary source of Mn.    

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Labile Al forms can be dangerous in acid soils due to their potential toxicity to plants. This paper deals with the distribution of exchangeable, weakly organically bound, and total organically bound Al forms in soils on 98 sites of the Jizera Mountains region. For the extraction of these Al forms, 0.5M KCl (Al KCl ), 0.3M CuCl 2 (Al CuCl 2 ), and 0.05M Na 4 P 2 O 7 (Al Na 4 P 2 O 7 ) solutions were used, respectively. Aluminium concentrations in all extracts were determined by means of ICP-OES. Following mean concentrations of Al forms were found in the O and B horizons (mg/kg): Al KCl -1236 and 832, Al CuCl 2 -4268 and 1945, and Al Na 4 P 2 O 7 -5043 and 8420. Basic soil characteristics were determined by commonly used methods. Their influence on Al forms distribution was assessed. Factor analysis showed that the most important soil factors controlling Al forms distribution were soil reaction and the total content of Ca (or Ca and Mg in the B horizon).