Can Plants Be Used To Clean Up Soils Contaminated By Crude Oil?

BP.jpgSadly, A Timely Topic

You’ve likely heard about microbes with the ability to “eat” crude oil (a.k.a., petroleum).

That is, some bacteria have the ability to metabolize most of the the organic compounds present in petroleum.

(For excellent scientific coverage of the oil spill see “The Science of the Oil Spill”.)

Interestingly, most of the bacteria used in the bioremediation of oil contamination are from natural populations, rather than genetically engineered in the laboratory.

But can plants help clean up the oil spill in the Gulf of Mexico?

That is, can plants, like some bacteria, take up and metabolize the organic components of crude oil?

Phytoremediation

Using green plants to help clean up (remediate) soils contaminated with toxic substances, such as heavy metals, radionuclides, or toxic organic compounds, is referred to as phytoremediation.

New_Wave.jpgThe use of plants to help clean up the environment has great appeal. The two main reasons why are (1) that the contaminated soils can be treated in situ and (2) that it’s relatively cheap, compared to conventional industrial clean-up methods. (The latter reason is, of course, very enticing to both government and industry.)

Though phytoremediation has a lot of promise, to date, it has had only limited success for several reasons.

Each contaminated site is different. Success in greenhouse studies often can not be replicated in the field, due to all the environmental and biological variables that occur.

Toxicity of site, especially with petroleum-contaminated soils, may kill most plants.

To breakdown toxic organic compounds in the soil, plants must by able to extract them. This is a major limitation.

The solution may be to use the plants’ roots as both a physical and nutritional “scaffolding” for microbes that can metabolize total petroleum hydrocarbons contaminants.

This is called “rhizoremediation”. Briefly, it takes advantage of the fact that plants can form symbiotic relationships with soil bacteria. (More about rhizoremediation later on)

Bottom line: The use of plants for phytoremediation of petroleum-contaminated soils is an emerging technology. Consequently, at the present time plants will likely play a limited role – at least directly – in remediating the Gulf oil spill.

References

1. Collins, Chris D. (2007) “Implementing Phytoremediation of Petroleum Hydrocarbons”, IN: Phytoremediation- Methods and Reviews, Methods in Biotechnology Vol. 23, pp. 99-108. Abstract

2. Gerhardt, K.E., X.-D. Huanga, B.R. Glicka and B.M. Greenberg (2009) “Phytoremediation and rhizoremediation of organic soil contaminants: Potential and challenges .” Plant Science Vol. 176, pp. 20-30. Abstract

3. Van Epps, A. (2006) “Phytoremediation of Petroleum Hydrocarbons”, Environmental Careers Organization, U.S. EPA. (PDF)

HowPlantsWork © 2008-2011 All Rights Reserved.

6 Comments

  1. Interesting post. I’ve heard similar theories that use fungi instead of plants to decontaminate soil.

    Your blog is really helpful. I’ll be visiting again, especially when I start up my gardening in the spring!

  2. thanks this is realy ggonna help me with science fair

  3. This website doesn’t say much at all. What plants? The amount of time it takes? I want details.

  4. No useful info here. WHAT PLANTS WORK???

  5. Wilhelm:
    I share your frustration…..Most plants don’t work on phytoremediation of terrestrial oil spills because the oil kills plants. Thus, there is a need to find (engineer?) plants that tolerate oil so that we can develop phytoremediation strategies. Funding anyone?
    There seems to be way more research funds available to produce “biofuels” from plants (to help perpetuate the internal-combustion-of-hydrocarbon-based-engines) compared to funding to use plants for phytoremediation of oil-contaminated soils.

Leave a Reply

Your email address will not be published. Required fields are marked *

*