a quantitative investigation on some toxic and non-toxic metals in popular medicinal herbs in iranian market

this study was performed to explore the presence of heavy metals in some popular herbal medicines of the iranian market. primarily, this study was planned to do the task by the usp method. in the second step, those plants which contained more than 10 ppm of total heavy metals were analyzed by atomic absorption method. in this study, 43 popular herbal medicines were investigated according to the limit test procedure in the usp. it was found that 27 of these plants contained less than 10 ppm heavy metals compared to a standard lead solution, while 16 contained more than 10 ppm. the presence of pb (<2.5), cd (<0.25), co (<1) and ni (<1.5) could be considered safe.