Phytoremediation of heavy metals contaminated water and soils from artisanal mining enclave using Heliconia psittacorum

Abstract

The activities of artisanal mining prevalent in most of Ghana has immensely contributed to the pollution of heavy metals and metalloids in both water and soils. This has resulted in the contraction of diseases associated with the ingestion of these pollutants. Aquatic plants have been recognised to be cost-effective and efficient means to remediate these pollutants from the environment. This study employed the use of Heliconia psittacorum in remediating soils polluted with heavy metals mercury (Hg), arsenic (As), cadmium (Cd) and lead (Pb). The remediation of these pollutants by H. psittacorum from polluted soil was studied in a greenhouse environment where the plants were grown. The irrigation of the plant was done with 10 ppm each of the heavy metals and metalloid. The roots and shoots of the plant were analysed of the number of heavy metals and metalloid absorbed by the plant after specific periods. There was high bio-absorption rate of As, Hg and Cd by H. psittacorum when each of the heavy metals/metalloids were the only contaminant in water as well as when all the four contaminants were together in the water. This means that the macrophyte can remediate As, Hg and Cd in soil and water. However, in the situation where the contaminants were paired in solution, there were synergistic effects on the metals uptake by the macrophytes, resulting in a low bio-absorption rate. This result indicates the fact that H. psittacorum can be used as one of the costs effective and green technology in remediating heavy metal contaminated soil/water.