Determination of some heavy metals in popular medicinal plants of Tehran ’s market

Abstract

Traditional medicines by medicinal plants have always played a key role in world health including Iran but<br />their safety profile is a major concern in this regard. In fact some factors such as the method of extraction,<br />contamination with microorganisms, existence of heavy metals, and pesticides may reduce the safety of<br />herbal based pharmaceutical products. The objective of this research was to determine the level of Cd, Pb, Ni,<br />Cu, and Hg as the major abundant heavy metals in some commonly used herbal medicines and herbal plants<br />of Iran's market. For this purpose, 10 samples from eight different commonly used medicinal plants were<br />collected from 10 different traditional stores in Tehran . Standardized international protocols were followed<br />for the preparation of material and analysis of heavy metals contents. An automated continuous flow hydride<br />vapor generation system was used for mercury determination . Atomic absorption spectroscopy (AAS) was<br />also used for the determination of the concentration of Pb, Cd, Ni and Cu. Results show that Cuminum had<br />the lowest Pb level and Syzigium cumin the highest. Cadmium concentration varied between 0.19- 9.26<br />ppm .Syzigium cumin, showed the highest Cd levels and Cuminum Cyminm showed the lowest levels. The<br />concentration of Cu varied from 8.15 to 73.28 ppm. Cordia myxa contained the highest levels of Cu and<br />Plantago psyllium contained the lowest levels. The highest level of Ni was detected in Myristica fragrams and<br />the lowest in Plantago psyllium. Although the Hg concentration was not detectable in Cuminum Cyminm and<br />Cordia myxa ,some samples showed 0.71 ppm. Out of all samples , Syzigium cumin showed the highest Hg<br />concentration. Environmental contamination with heavy metals is one of the major concerns in developing<br />countries therefore regular controls on these plants should be perfomed by the government .It seems that<br />using cultivated plants under controlled conditions can the level of contamination.