Phytoremediation Potential of Plants Growing in a Mined-out Area at Afiesa in the Eastern Region of Ghana

Phytoremediation provides a cost-effective means of removing/reducing heavy metal contamination in the soil using plants. This study investigated the phytoremediation capabilities of 11 plant species growing in a mined-out area at Afiesa, a neighbouring town of Kyebi Apapam, in the Eastern Region of Ghana. Plant species and soil samples (composite and reference) were collected and analysed for total arsenic (As), copper (Cu) and lead (Pb) content. The outcome of the study showed different accumulating potentials of various plant species for different metals/metalloids. Three plant species (P. calomelanos, S. jamaicensis and T. orientale) with a BAF > 1, showedbioaccumulation potential for As and hence can be used for phytoextraction of As. Also, A. cordifolia showed a whole plant bioaccumulation for Cu >1 and hence can be used for phytoextraction of Cu. Among the plant species investigated, B. textilis (1159.5 mg/kg), P. calomelanos (2167.5 mg/kg), S. torvum (1923.5 mg/kg), S. jamaicensis (1350 mg/kg) and T. orientale (1669.5 mg/kg) demonstrated hyperaccumulation for Pb. Some of the analyzed plant species demonstrated selective upward transfer (translocation factor) of heavy metals showing their varied capabilities in translocating the absorbed heavy metal to aerial part of the plant (phytotranslocators). It can be concluded that B. textilis, P. calomelanos, Solanum torvum, Stachytarpheta jamaicensis and Trema orientale are potential phytoaccumulatos of Pb whereas P. calomelanos, S. jamaicensis and T. orientale can be used for phytoextraction of As. Due to the limitation of the current study, it is recommended that a potted study can be carried out to test the phytoextraction dynamics with respect to time. Also, genome analysis can be carried-out on the plants to identify metal-extracting genes.