Health risk assessment of heavy metals (As, Al, Zn and Cu) in lemon balm and borage Marketed in Hamedan City

Background and Medicinal plants are importance in the both approach of treatment and prevention of diseases in human societies. In recent years, due to the adverse effects of chemical drugs and their side effects, tendency to use of medicinal plants have increased. But due to the possibility of some toxic elements in medicinal plants, this study was carried out for analysis and health risk assessment of As, Al, Zn and Cu in lemon balm and borage marketed in Hamedan City in 2015.
After preparation of four samples of each medicinal plant and acid digestion of the samples according to standard methods, the concentration of elements in samples was determined using inductively coupled plasma-optical emission spectrometry (ICP-OES) in three replicates. Also, all statistical analyses were performed using the SPSS statistical package.
The results showed that the maximum mean concentrations of As, Al, Zn and Cu in plant samples were 0.175 ± 0.07, 13.93 ± 5.50, 0.34 ± 0.18 and 0.25±0.08 mg/kg, related to lemon balm respectively. However, the mean concentration of Al in lemon balm samples was upper than WHO maximum permissible limits (MPL), but health risk assessment showed that no potential risk for children and adult by consume the studied herbal plants.
Although controlled consumption of medicinal plants has not adverse effect on the consumers’ health, but concerning increased use of agricultural inputs, sewage sludge and wastewater by farmers, regular periodic monitoring of chemical pollutants content specially heavy metals in foodstuffs are recommended for food safety.