%0 Journal Article
%T Levels of metals in commercially available Ethiopian black teas and their infusions
%A Daniel Woldegebriel Gebretsadik
%A Bhagwan Singh Chandravanshi
%J Bulletin of the Chemical Society of Ethiopia
%D 2010
%I Chemical Society of Ethiopia
%X K, Ca, Mg, Mn, Fe, Zn, Cu, Co, Cd and Pb contents of commercially available Ethiopian black tea (Wushwush, Gumero, and Black Lion) and their infusions were analyzed by flame atomic absorption spectrometry (FAAS). In black tea leaves the order of metal content was found to be: K (11503每13780 mg/kg) > Ca (3821每4419 mg/kg) > Mg (3219每3538 mg/kg) > Mn (1242每1421 mg/kg) > Fe (319每467 mg/kg) > Zn (20.2每21.6 mg/kg) > Cu (9.1每11.5 mg/kg). Co, Cd and Pb were too low to be detected by the method (FAAS). In tea infusion, prepared in a laboratory condition following Ethiopian tea making procedures, the range of metal contents was found as follows: K (110每124 mg/L) > Mg (14.5每16.3 mg/L) > Ca (10.0每10.7 mg/L) > Mn (8.5每13.4 mg/L) > Fe (0.98每1.56 mg/L) > Zn (0.098每0.100 mg/L) > Cu (0.038每0.063 mg/L). The metal contents of the black tea leaves were higher than those of tea infusions. The extraction was highest for K (47.1%) and lowest for Ca (12.5%). KEY WORDS: Tea (Camellia sinensis), Black tea, Tea infusion, Heavy metals, Flame atomic absorption spectrophotometer (FAAS)   Bull. Chem. Soc. Ethiop. 2010, 24(3), 339-349.
%U http://www.ajol.info/index.php/bcse/article/view/60664