Ability of phytoremediation for absorption of strontium and cesium from soils using Cannabis sativa

Aims: This study is aimed at assessing the effectiveness of Cannabis sativa in the absorption of cesium and strontium elements from the soil. Materials and Methods: This study was conducted in 2011, in Tehran, Iran. We employed the phytoremediation technology to refine the contamination of soil with radioactive material such as cesium and strontium. Cannabis sativa was selected because of its capability for potential radioactive absorption. It was planted in various soils with different concentrations of cesium and strontium (20 ppm, 40 ppm, 60 ppm, and 80 ppm), and after sufficient growth for about six months, it was separated into root, stem, and leaves for measuring the absorption of these elements in the main parts of the plant. The samples were measured by using the Inductively Coupled Plasma (ICP) method. Results: Strontium absorption and the main parts of the plant showed a significant relationship. The percentage of strontium absorption was 45% in the root, 40% in the stem, and the minimum absorption was found in the leaves (15%), but the corresponding figure was not significant for the cesium element. A strontium concentration of 60 ppm was possibly the maximum absorption concentration by Cannabis. Conclusion: Our findings suggest that strontium can be absorbed by Cannabis sativa, with the highest absorption by the roots, stems, and leaves. However, cesium does not reach the plant because of its single capacity and inactive complex formation.