African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6688

Full Length Research Paper

Trace metal concentrations in some tea leaves consumed in Ibadan, Nigeria

Modupe O. Dawodu, Samuel O. Obimakinde and Godwin O. Olutona*
Department of Chemistry and Industrial Chemistry, Bowen University, Iwo, Osun State, Nigeria.
Email: [email protected], [email protected]

  •  Accepted: 13 November 2013
  •  Published: 30 November 2013


This study was conducted to determine concentrations of seven trace metals and proximate analysis of some teas consumed in Ibadan, Southwestern Nigeria. Standard methods described by Association of Official Analytical Chemist (AOAC) were used for proximate analysis, while Flame Atomic Absorption Spectrometer (FAAS) was used for metal quantification. The mean of proximate analysis (%) were as follows: Nitrogen (3.01 ± 0.08), Protein (18.85 ± 1.87), Fat (4.63 ± 0.09), Ash (10.79 ± 1.42), and moisture content (8.40 ± 0.11). The ranges of the essential elements in percentage are as follows: Calcium (1.91 to 7.99), Potassium (0.90 to 2.91) and Magnesium (0.33 to 0.62), while the ranges for trace elements in µg/g are as follows: Copper (7.36 to 10.93), Iron (180.38 to 320.04), Manganese (104.78 to 117.85) and Zinc (21.17 to 40.00). Though the trace metals do not constitute any health risk at the present, regular monitoring of their levels in tea plant is necessary for future risk assessment.


Key words: Atomic absorption spectrometry, proximate analysis, tea, trace metals.