Phytoremediation: Mechanisms, plant selection and enhancement by natural and synthetic agents

With current intensive agriculture practices and industrialization, pollution of natural resources like land and water with heavy metals, organic pollutants, radionuclides, pesticides, and fertilizers has become a major concern. Phytoremediation is a cost-effective and environmentally friendly technique that utilizes plants to immobilize, uptake, reduce toxicity, stabilize, or degrade the compounds that are released into the environment from different sources. Studies have shown that heavy metals, organic contaminants, radionuclides, antibiotics, and pesticides can be remediated using plants. Though phytoremediation has been practiced since decades, it is still an emerging technology. This review article summarizes existing information and synthesizes the recent findings on plant species suitable for use in phytoremediation through utilizing different mechanisms, aids that can enhance the efficiency of phytoremediation processes, and strengths and limitations that comes with the application of this technique. Diverse plants remediate different pollutants at different rates through one or multiple mechanisms. The limitations of phytoremediation can be overcome by using several aids including natural and chemical amendments, genetic engineering and natural microbial stimulation. Given the low-cost of phytoremediation compared to conventional technology and sustainability associated with plants and use of renewable energy, phytoremediation can be a reliable solution for a sustainable and economical remediation of soil and water from the organic and inorganic pollutants.