A Multi-disciplinary Challenge for Phytoremediation of Metal-Polluted Pyrite Waste

After the discovery of hyperaccumulators plants which accumulate high above-ground levels of one or a few metals without evident symptoms of toxicity, the application of plant-based technologies to remedy metal-contaminated soils has received huge attention. Metalliferous soils provide several hyperaccumulators, but their application must be verified carefully in terms of biomass—generally very small—and uptake when plants are cultivated out of their native environment. Phytoextraction consists of removing toxic elements through the harvestable biomass, after sufficient translocation from roots has occurred. Although promising, the method has some limitations due to difficult plant establishment, possible limited soil metal availability, insufficient root uptake (exclusion), symplastic mobility and xylem loading, as well as the great energy costs required for detoxification and storage.