Heavy metal constituent of medicinal plants: a case study of Moringa oleifera Lam. from  selected areas s compromise the quality of medicinal plants? A case study of Moringa oleifera Lam. from some selected areas in the Accra, Ghana.

Michael Lartey; Samuel Frimpong-Manso; Prince Osei Banahene; Adolphina Addo-Lartey; Nathaniel Nii-Adu Okine; Daniel Boamah; Awan AR Mohammed

doi:10.46829/hsijournal.2021.6.2.1.181-188

Michael Lartey Department of Pharmaeutical Chemistry, School of Pharmacy, College of Health Sciences, University of Ghana, Accra, Ghana.
Samuel Frimpong-Manso Department of Pharmaeutical Chemistry, School of Pharmacy, College of Health Sciences, University of Ghana, Accra, Ghana.
Prince Osei Banahene Department of Pharmaeutical Chemistry, School of Pharmacy, College of Health Sciences, University of Ghana
Adolphina Addo-Lartey Department of Epidemiology and Disease Control, School of Public Health, College of Health Sciences, University of Ghana, Legon, Ghana
Nathaniel Nii-Adu Okine Department of Pharmaceutical Chemistry, School of Pharmacy, University of Health and Allied Sciences, Ho
Daniel Boamah Ghana Geological Survey Authority, Accra, Ghana.
Awan AR Mohammed Ghana Geological Survey Authority, Accra, Ghana.

DOI: https://doi.org/10.46829/hsijournal.2021.6.2.1.181-188

Keywords: Anthropogenic, herbal medicine, Moringa oleifera, soil-plant transfer factor, Ghana

Abstract

Background: Anthropological activities release metals into the environment and could be absorbed by plants and assimilate into herbal medicines.

Objective: This study seeks to correlate the outcome of anthropogenic activities that release metals into the environment with levels of metals in herbal plants using the leaves of Moringa oleifera (M. oleifera) as a case study.

Method: Leaves of M. oleifera Lam. and soil around sampled plants were collected from three locations in the Accra Metropolis: a commercial, densely vehicular traffic area, and a quasi-natural habitat. Samples were analyzed with Energy Dispersive X-ray Fluorescence (ED-XRF) spectroscopy for the presence and levels of arsenic (As), cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), vanadium (V) and zinc (Zn). Statistical analyses were performed and the correlation between metal concentrations in leaves and soil was assessed using Spearman’s correlation coefficient.

Results: Leaves and soil samples contain varying amounts of the metals. Levels of metals in leaves were significantly lower than permissible limits (p < 0.05). Translocation factor (TF) estimates, indicated that the M. oleifera leaves exclude metals. However, the TF > 1 in the case of Zn from the quasi-natural habitat signifying bioaccumulation in the leaves. Except for Co, the total concentration of each metal in the soil was not correlated to its concentration in the leaves. However significant correlations were observed between concentrations of some metals in the leaves and also in the soil.

Conclusions: The concentration of sampled metals in the leaves and soil are affected by the site of sampling and the anthropogenic activities that release metals into the environment.