Can Oil-Eating Mushrooms Clean Up After a Spill?
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The chance to study this process outside the lab came a year later, when the Washington State Department of Transportation partnered with Stamets and the Battelle Marine Science Laboratory to compare different cleanup methods at a maintenance yard contaminated with diesel fuel. Workers scooped piles of the toxic soil onto tarps, and each pile was inoculated, either with a form of oil-eating bacteria or with Stamets’ mix of oyster-mushroom mycelia and wood chips.There were also several control patches of soil.
Again, the results were encouraging. The bacterial patches, Stamets says, remained “dead, dark, and stinky.” Same with the control group. Meanwhile, his own patches were teeming with huge oyster mushrooms feasting happily on the diesel compounds. “Analyses showed that more than 95 percent of many of the PAHs … were destroyed,” Stamets wrote, “and the mushrooms were also free of any petroleum products.”
Because the contamination in the soil patches was very uneven, it was difficult to measure the precise concentration of contaminants both before and after remediation. However, researchers at the Department of Transportation eventually declared the fungi-cleansed soil pure enough to use for landscaping purposes along the highways of Washington. And in the years since, Stamets’s findings have been replicated by many other researchers, and further study has shown that various types of fungi are able to partially or fully detoxify oil and pesticides. Geoffrey Gadd of the University of Dundee, Scotland, even found that fungi can break down depleted uranium from anti-tank shells by allowing it to bond with phosphates to form a more stable mineral.
Since the Deepwater Horizon spill in April 2010, Stamets has been testing his oyster mushrooms for tolerance to salt water and sun in preparation for a gig off the coast of Texas or Louisiana. So far, he’s managed to isolate a strain that can tolerate the salinity of Puget Sound, which is only slightly less than that of the Gulf. And he’s found ways to float the mushrooms cheaply on hemp “mycobooms” filled with straw and mycelia from which the mushrooms can metabolize oil on the surface of the sea.
Stamets says this new research is “very cool and unlikely to have been discovered if it were not for this disaster.” He believes it will be used in the near future and has applied for a provisional patent to prevent oil companies from stealing the research. But he says he would be happy to share it for free with affected communities in the Gulf of Mexico.
More Mushrooms, Less Waste
Eating oil turns out to be just one of many practical applications for fungi. Stamets has demonstrated that they offer cheap and sustainable solutions for encouraging the healthy growth of plants, controlling insect pests, filtering farm waste, and creating medicines to treat human diseases.
Several of Stamets’ projects take advantage of the symbiotic relationships that exist between fungi and plants. Certain fungi intertwine themselves with the roots of plants, taking nutrients from them while protecting the plants from attack. Fungi can also make a plant hundreds or even thousands of times more efficient at gathering water and minerals from the soil.
Stamets’ company, Fungi Perfecti, manufactures an alternative to fertilizers called Mycogrow, which some organic farmers say provides them with huge and healthy crops without creating pollution.
Another product based on the same principle is the LifeBox, a package made from recycled cardboard that contains the seeds of common trees paired with the spores of specific fungi that partner with them in old-growth forests. You use the box for shipping; the recipient tears it up and buries it in the ground. A cobweb-like growth of white mycelia will appear on the surface a few days later. This fungal network “mothers the seed nursery by providing nutrients and water,” according to the project’s website, “thus protecting the growing trees from disease, drought, and famine.”