Mycoremediation - The Power of Mushrooms

A little paper I wrote for my Permaculture Design Course back in 2007.

"Mycoremediation" is a new term for a process that has been occuring
for millions of years, and is now being proposed, by some, as a
powerful tool for the remediation of soil and water contaminated by
man-made toxic pollutants. The most visible public presentation of
the idea comes from mushroom guru Paul Stamets, in his 2005 book,
Mycelium Running. I decided to see if this "new" idea was yet being
applied, and if not, why. I was also interested in finding out where
research was happening, as I might be looking for a graduate school
program in the near future. What follows is a brief summary of some
highlights from my research findings, which included a broad overview
of mycoremediation. A large list of leads on research groups and
firms were amassed and are at some degree of organization at this
point.
Fungi, as decomposers, have the ability to digest plant-based
molecules. A wide range of man-made compounds are synthesized from
oil, a substance produced by ancient plant material. Some of the most
dangerous toxins; PCB's, Dioxins neurotoxins and even TNT, to name a
few, apparently resemble natural plant molecules enough to be digested
by fungi present in the soil. The wood-digesting house-wreckers known
as brown and white rot, together with the oyster mushroom and A. niger
are seemingly the most popular candidates for use in mycoremediation.
Stamets stresses the idea that the best place to look for powerful
remediating fungi is at site of contamination. Mycologists and other
field researchers have, in fact, isolated a large number of species
capable of breaking down contaminants.
After reading Mycelium Running, one gets the impression that this
field of remediation is a rising science, about to break through to
popular application. However, it appears that Paul Stamets remains to
be the most vocal proponent of mycoremediation, at least in the public
realm. In his book, he even proposes one major hurdle to widespread
application: many of the techniques of mycoremediation are subject to
patent protection. Stamets, himself, holds several patents. Since
most contaminated sites are polluted by many several contaminants, its
easy to inadvertently step on toes.
Although there appears to be no formal graduate programs in
mycoremediation, there are a great many research groups within the
academic realm, studying the degradative powers of fungi. They
publish in journals like "International Biodeterioration and
Biodegradation", "Bioremediation Journal," and "Applied
Microbiological Biotechnology." Much of this work is in the
laboratory, using single contaminants in control conditions. However,
a search for recent articles with keywords "soil bioremediation"
returned almost 200 articles in the last year. Many reviews of the
literature close with remarks to the effect of "this promising field
lacks outdoor trials" or "the fate of pollutants in the ecosystem is
unknown."
According to a book "Biotechnology for the environment: Soil
remediation," bioreactors are already being used at an industrial
scale in Germany to clean soil contaminated with PAHs (persistent
aromatic hydrocarbons). The book outlines several bioprocess
techniques, most relying on the indigenous fungal community of the
soil, and gives the impression of demonstrated viability of industrial
application of some types of mycoremediation.
As a matter of coincidence: during my trip to the Bay area in
California, a recent oil spill in San Francisco was being cleaned up
using oyster mushrooms. Not surprisingly, Paul Stamets was the one
supplying the innoculant and consultation on this project, for the
non-profit organization, matter of trust. Activists trespassed on the
restricted site of the oil spill in order to absorb the slicks with
mats of human hair, which are now being digested by oyster mushrooms.
There seems to be a general consensus that mycromediation is
promising tool for future regeneration of ecological systems. It is a
noteworthy consideration for students of the regenerative science of
permaculture. It will be interesting to see how the field develops.
Fortunately, the patents are only good for 17 years.
The research for this project was conducted mostly using the internet
and the library resources at my alma mater, Worcester Polytechnic
Institute. Using interlibrary loan, I ordered Mycelium Running and
several other books found through internet searches for books on
"mycoremediation" or "bioremediation." One particularly helpful
research tool is Google scholar, which searches academic books and
papers. Science Direct was another useful tool to find recent papers.

Resources:

S. Agathos and W. Reineke, eds. (2002) Biotechnology for the
Environment: Soil Remediation
-offers a look at industrial application of bioreactors and bioremediation
Harbhajan Singh (2006) Mycoremediation: Fungal Bioremediation
-an encyclopedia of research on the degradative powers of fungi, heavy
on science
Paul Stamets (2005) Mycelium Running: How Mushrooms Can Help Save the World
-well-known and inspiring book on the power of mushrooms