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

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