Bioaccumulation coefficients of roots of most plants are also known to be relatively much higher than those for shoots. Rhizofiltration provides a cheap method of clean-up for low concentration of contaminants in large volumes of water, so that for radionuclide contaminated waters, it may be particularly suitable, more so when used in combination with micro-organism based bioremediation strategy.

A number of plant species including rapeseed mustard (B. juncea), rye, corn and sunflower can have rapidly growing roots and can be used for rhizofiltration. Different metals are removed by roots, perhaps utilizing different mechanisms. For instance, in case of Pb, passive surface absorption (e.g. chelation, ion exchange and specific adsorption) by the roots (living or dead) is the fastest method of metal removal. Other biological processes including intracellular uptake, vacuolar deposition, and translocation to the shoot are relatively slower. Root mediated precipitation of Pb in the form of Pb phosphate is the slowest process. Cell walls of roots can also accumulate Pb in the form of PbCO₃ formed due to respiratory CO₂.