Determination of As, Cd, Hg and Pb elemental levels in some medicinal plants sold in Diyarbakır herbalists by ICP-MS

Aim: Medicinal plants grown in many regions of our country have an important role in human health. The purpose of our study is to determine and compare the levels of As, Hg, Cd and Pb in studied plants and their infusions; and also statistically to evaluate both acid dissolved and infused forms of plants. The studied plants sold in Diyarbakır herbalists which are herba equiseti, hibiscus, quince leaves, salvia, rosemary, stinging nettle, lady's mantle, linden, senna, fennel, mint, flax seed, aaron's beard, carob, green tea, licorice, bluberries; are commonly used as treatment in many diseases and as spices by local people. Material and Method: The amounts of As, Hg, Cd and Pb in the medicinal plants and their infusions were analyzed by ICP-MS technique after dissolution of plants with concentrated nitric acid and hydrogen peroxide in microwave system. The accuracy and precision of the method were evaluated using CRM 1515 apple leaves. Moreover our results were statistically evaulated by using "Paired T Test", "Wilcoxon T Test", "Spearman Correlation Analysis" and "Shapiro-Wilk Analysis" in SPSS-21. Results: It was determined that As, Hg, Pb and Cd values of the studied plants and infusions are below the limit values determined by WHO; only distrubition of Pb datas were normal (p> 0,05) and there are a statistically significant difference in the amount of Pb element between the plant and infusion samples (p <0,05); in all plants, As and Hg concentrations were higher than infusion samples, however only Cd concentrations were higher than 15 infusion samples. Conclusion: It was concluded that heavy metal levels in studied plants are suitable for consumption as medicinal herbs and herbal tea; since they are below the limit values determined by WHO. However, it was resulted that medicinal plants should be consumed as consciously dose-controlled. Keywords: Medicinal plants, Heavy Metals, ICP-MS, Paired T Test, Wilcoxon T Test