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Please use this identifier to cite or link to this item: http://hdl.handle.net/123456789/2435

Title: Determination of trace metals in commercially available Khat (Catha edulis Forsk) in Addis Ababa
Authors: Ephrem, Tilahun
Advisors: Dr.Merid Tessema
Keywords: Flame Atomic Absorption Spectrometry
Trace metal
Adiss Abeba
Khat (Catha edulis Forsk)
Copyright: Jun-2009
Date Added: 4-May-2012
Publisher: AAU
Abstract: Khat (Catha edulis Forsk) is a plant that grows in certain areas of East Africa and the Arab Peninsula. A large number of people in Ethiopia chew khat leaves because of its pleasurable and stimulating effects. In the present study the level of selected Trace metals ( Cu, Zn, Mn, Ni, Co, Cr, Cd and Pb) in four different kinds of khat sampled from different khat shops in Adiss Abeba were analyzed. Known weights of oven dried Khat samples were digested by wet digestion using 3 mL of HNO3 ,1 mL of HCLO4 and 1 mL of H2O2 by setting the temperature first to 60 0C for 30 min and then increased to 210 0C for the next 2 h and 30 min. The contents of the minerals in the digests were analysed using flame atomic absorption spectrometry. The following concentration ranges in dry weight (μg/g) were obtained in the khat samples: Cu (19.2 - 24.4); Zn (24.1 – 46.9); Mn (14.92 – 20.6); Ni (4.7 – 7.7); Co (3.1 – 7.76); Cr (3.1 – 6.76); Cd (1.3 – 2.9) and Pb (4.8 – 9.1). Among the essential metal analyted Zn was the most abundant one followed by Cu,Mn,and Ni Whereas Co and Cr were less than Pb. Generally ‘Bahirdar’ Khat contained higher concentration compared to Gelemso, Gurage and Wondo for the majority of the mineral nutrients identified. The tested four kinds of khat proved high variability (p<0.05) in their content of trace metals. The possible uptake by the human body from fresh khat has also been determined. Except Cd and Pb the amount of metal that one may take through consumption of fresh khat alone were found to be below the recommended daily allowance
URI: http://hdl.handle.net/123456789/2435
Appears in:Thesis - Chemistry

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