Phytoremediation: A Green Technology with Weeds as Actors in Heavy Metal Contaminated Soil

Abstract

Background: Soil contamination by toxic metals leads to major ecological and human health problems. The metals are non-degradable and accumulate in the environment. It is therefore necessary to source for sustainable measures to remediate contaminated soils. Phytoremediation is a promising technology that involves the use of green plants to tidy up sites sullied with toxic pollutants. This paper highlights weeds as plants to be exploited for the remediation of heavy metal contaminated soils. Methods: Research materials related to phytoremediation techniques and soil contamination by heavy metals are reviewed. The sources and toxicity of these metals are indicated. The various techniques for phytoremediation, properties of plants that are suitable for use and some weeds with the potential are outlined. Results: Soil contamination by heavy metals is an issue of serious concern mostly in the developing countries. It is a threat to plants and underground water, and there is a possibility for these toxic substances to be incorporated into the food chain. Some of these metals accumulate in body organs and cause severe damage. Conventional technologies for the remediation of soils contaminated by these toxic metals are costly and time consuming. Several species have been reported with phytoremediation potential, though information is scarce in developing countries. Conclusion: Phytoremediation is a feasible method to clean up contaminated soils because it is sustainable, inexpensive and environmentally safe. Weeds are fast growing plants that produce high biomass and this makes them suitable for use in phytoremediation. Keywords: Contamination, green plants, heavy metals, phytoremediation, soil, weeds.