|
Decontaminate soils
by extracting and
degrading pollutants
Phytoremediation
is the use of
plants and their
associated
microbes for the
cleanup of
toxics and
pollutants in
soils and
groundwater.
Soil remediation
is a huge
challenge, as
human activities
have left behind
many organic
pollutants
(petroleum
derived
hydrocarbons,
pesticides,
organic
solvents, etc.)
and inorganic
pollutants
(heavy metals,
selenium, etc.)
in the
environment.
Plants can
remediate
pollutants via
stabilization,
degradation (in
the root
environment or
within the plant
tissues),
accumulation in
harvestable
organs or
volatilization.
They open up new
possibilities
for large scale,
cost-effective
cleanup
strategies that
are gaining
increasing
popularity from
public agencies
and industry.
Molecular
physiology
studies over the
last 10 years
have provided
insight into the
diverse
mechanisms of
pollutant
tolerance,
accumulation and detoxication, in
naturally
tolerant plants
and in model
organisms. Gene
transfer
technology
which enabled
the modification
of plants to
cope with toxics, like the
conversion of
Arabidopsis
plants into
mercuric
ion-tolerant
plants, turned
plants into phytoextractors
of very noxious
compounds.(1)
More recently,
the concept has
been extended to
field plants,
with GM Indian
mustard
tolerating and
extracting
selenium from
contaminated
sediments.(2)
Organic
pollutants,
called xenobiotics, can
also be
remediated by
plants and
poplar is an
example of
a species which
efficiently
takes up some
solvents and
pesticides via
the
transpiration
stream and
degrades or
volatilizes them.(3)
Such ‘green
clean’
technologies
tend to be much
cheaper than the
alternatives and
they can be
integrated into
attractive
landscape
management
policies.
1.1)
Ruiz ON, Hussein
HS, Terry N, Daniell H
(2003).
Phytoremediation
of
organomercurial
compounds via
chloroplast
genetic
engineering.
Plant Physiology
132: 1344-1352.
2) Banuelos G.,
Terry N., LeDuc
D., Pilon-Smith
E., Mackey B.
(2005). Field
trial of
transgenic
indian mustard
plants shows
enhanced
phytoremediation
of
selenium-contaminated
sediments. Environmental
Science and
Technology. 39:
1771-1777.
3)
Pilon-Smits E.
(2005).
Phytoremediation.
Annual Review of
Plant Biology.
56: 15-39.
 back
|
|
|
 |
|
|
Briefs
and Policy Reports |
