What is Bioremediation and phytoremediation?

Bioremediation can be defined as any process that uses microorganisms, fungi, green plants or their enzymes to return the environment altered by contaminants to its original condition

Phytoremediation describes the treatment of environmental problems (bioremediation) through the use of plants.

Advantages and limitations
Advantages:
- the cost of the phytoremediation is lower than that of traditional processes both in situ and ex situ
- the plants can be easily monitored
- the possibility of the recovery and re-use of valuable metals (by companies specializing in “phytomining”)
- it is the least harmful method because it uses naturally occurring organisms and preserves the natural state of the environment.

Limitations:
- phytoremediation is limited to the surface area and depth occupied by the roots.
- slow growth and low biomass require a long-term commitment
- with plant-based systems of remediation, it is not possible to completely to prevent the leaching of contaminants into the groundwater (without the complete removal of the contaminated ground which in itself does not resolve the problem of contamination)
- the survival of the plants is affected by the toxicity of the contaminated land and the general condition of the soil.
- possible bio-accumulation of contaminants which then pass into the food chain, from primary level consumers upwards.

The role of genetics
Breeding programs and genetic engineering are powerful methods for enhancing natural phytoremediation capabilities, or for introducing new capabilities into plants. Genes for phytoremediation may originate from a micro-organism or may be transferred from one plant to another variety better adapted to the environmental conditions at the cleanup site.

Adapted from http://en.wikipedia.org/wiki/Phytoremediation