Determining the concentration of Ag, Pb and Zn elements in some indigenous plant species grown in Zarshouran mining area, northwestern Iran

Phytoremediation is one of the eco-friendly treatment methods that can play important role in removing heavy metals. In the present research that was done in 2021, the potential of 20 plant species for treatment of silver, lead, and zinc elements from the soil of Zarshouran mine area was evaluated.  

Sampling of the soil and plants were done following the selection of 20 sampling points. After preparing the samples, the amount of the studied elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). Metal pollution levels in the soil were assessed using the enrichment factor (EF). Moreover, the enrichment coefficient of root (ECR) and shoot (ECS), translocation factor (TF) and metal accumulation index (MAI) were calculated.

A high contamination of Ag, Pb and Zn elements were determined in the soil of the studied area. Two plant species Astragalus rostratus and Prangos ferulacea had ECS and TF higher than one for Ag. Also, only Eryngium billaridieri and Scrozonera latifolia had ECS/ECR >1 and TF <1 for the three elements. The highest amount of MAI in root and shoot belonged to E. billardieri with values ​​of 29.7 and 16.2, respectively.

A. rostratus and P. ferulacea had the potential for phytoextraction of Ag from the soil. Also, only two species E. billaridieri and S. latifolia were able to phytostabilization all three elements. Based on MAI values, E. billardieri had the greatest ability to bioaccumulate Ag, Pb and Zn elements.