Phytoremediation-a green approach to environmental clean-up

Acute and diffuse contamination of soil and water by heavy metals, radionuclides, explosives and organic/inorganic pollutants have caused extensive, environmental and social concerns across the globe. Among the techniques used for cleaning up environmental pollution, phytoremediation has emerged as a more recent innovative, cost-effective and environment-friendly alternative. Phytoremediation utilizes plants and microbes to remove, transform or stabilize a whole lot of contaminants in water bodies, sediments or soils. This review focused on the types, advantages and limitations of current state of knowledge and future directions of plant-based cleanup techniques. Phytoremediation technologies included phytoextraction, phytostabilization, phytodegradation, phytostimulation and rhizofiltration. Phytoremediation also had limitations especially when toxicity levels and bioavailability of the pollutants limited its applicability. Or, long cleanup periods had been the greatest shortfall of phytoremediation. The past years had seen notable advances in understanding hyperaccumulator plant selection and breeding; processes that affected pollutant availability, rhizosphere processes, pollu-tant uptake, translocation, degradation and volatilization. There had, however, been still areas that were quite underdeveloped. To further enhance the efficiency of phytoremediation, a number of research directions needed attention. These included molecular biology and genetic engineering in breeding hyperaccumulators, agronomic practices for maximized pollutant uptake by plants, mechanisms of plant-microbe interactions in rhizosphere, integrated remediation technologies, field validated remediation efficiency, integrated landscape architecture, and bioenergy/seeding production of ornamental plants.