@article {630, title = {The Heavy Metal Contents of Some Selected Medicinal Plants Sampled from Different Geographical Locations}, journal = {Pharmacognosy Research}, volume = {5}, year = {2013}, month = {April 2013}, pages = { 103-108}, type = {Original Article }, chapter = {103}, abstract = {

Background:\ The levels of 5 minerals namely; lead, arsenic, mercury, cadmium, and aluminum were assessed in 10 medicinal plants sampled from 5 different geographical locations to determine the effect of location on the plants{\textquoteright} mineral content.\ Materials and Methods:\ Atomic absorption spectrophotometry (wet digestion) was used for the analyzes, and content of the minerals per sample was expressed as μg/g. The levels of minerals were compared to their limit specification for herbs and daily total intake of these minerals. A two-way analysis of variance, which tends to look at the effect of the location and the medicinal plant itself on the plants mineral content, was used in the statistical analysis.\ Results:\ Lead (Pb) was present in all plant species examined, except\ Ocimum gratissimum. One plant exceeded the maximum safety limit for lead. Cadmium was also detected in some of the medicinal plant species (44\%) whilst majority were below the detection limit (0.002) representing 56\%. 40\% of the plant species exceeded the limit for cadmium. Mercury and arsenic in all the plant species were below the detection limit (0.001). Significant variation existed in mineral content for the various locations (\ P\ <= 0.05).\ Conclusion:\ The findings generally suggest the variation in mineral levels for the various locations. Thus, our study has shown that same species of medicinal plants, growing in different environments, accumulates different levels of heavy metals.

}, keywords = {Geographical Locations, Heavy metals, Medicinal plants, Minerals}, doi = {10.4103/0974-8490.110539 }, author = {Kofi Annan and Rita A Dickson and Isaac K Amponsah and Isaac K Nooni} } @article {758, title = {Profile of Heavy Metals in Some Medicinal Plants from Ghana Commonly used as Components of Herbal Formulations}, journal = {Pharmacognosy Research}, volume = {2}, year = {2010}, month = {March 2010}, pages = {41-44}, type = {Original Article}, chapter = {41}, abstract = {

The levels of some heavy metals in 27 medicinal plant species from Ghana were studied in order to evaluate their health implications. These plant species, especially those used in the treatment of diseases such as hypertension, diabetes and asthma may require long term usage. The metals were copper, zinc, iron, manganese, nickel and cadmium. Atomic Absorption Spectrophotometry (wet digestion) was used for the analyses, and content of metals per sample was expressed as percent {\textmu}g/g. Daily total intake of these metals is discussed based on the recommended daily intake of the medicinal plants or their corresponding formulations. From the results of the study zinc, copper and cadmium were present in all the plant species examined. Manganese was present in all species except V. amygdalina. Iron was found in all except five species (82\%), whilst nickel was (rather rare) detected in only eight (30\%) of the plant species. Significant variations in metal content existed (P\<0.05) among the medicinal plant species with respect to the heavy metals evaluated. The concentrations of copper, zinc, cadmium and manganese were within their respective maximum permissible daily levels. However, some species, especially Ocimum canum (8), Clausena anisata and Rauwolfia vomitoria had levels of iron higher than the maximum permissible level of 1000 {\textmu}g/day and may require care to avoid iron toxicity. The results also highlighted the differences in contents of minerals in Lippia multiflora obtained from different locations in Ghana. The findings generally suggest that the use of these plant species for the management of diseases will not cause heavy metal toxicity and may be beneficial to the users in cases of micronutrient deficiency, as these metals were found to be present in readily bioavailable form.

}, keywords = {Health implications, Heavy metals, Herbal formulations, Mdicinal plant}, doi = {10.4103/0974-8490.60579}, author = {Kofi Annan and Asante Isaac Kojo and Asare Cindy and Asare-Nkansah Samuel and Bayor Marcel Tunkumgnen} }