Tuesday, July 5, 2011
When BP spilled huge quantities of oil into the Gulf, the company and the government ignored natural ways to help clean up the mess, and instead dumped toxic dispersants into the Gulf which actually made things worse.
Likewise - believe it or not - there may be natural ways to help clean up radiation from Fukushima and elsewhere, and to reduce human and animal exposure to radioactive elements.
Scientific American points out:
Like plants that grow toward the sun, dark fungi, blackened by the skin pigment melanin, gravitate toward radiation in contaminated soil. Scientists have observed the organisms—somewhere between plants and animals—blackening the land around the Chernobyl Nuclear Power Plant in Ukraine in the years since its 1986 meltdown. "Organisms that make melanin have a growth advantage in this soil," says microbiologist Arturo Casadevall of the Albert Einstein College of Medicine in New York City. "In many commercial nuclear reactors, the radioactive water becomes contaminated with melanotic organisms. Nobody really knows what the hell they are doing there."
"Melanin is very good at absorbing energy and then dissipating it as quickly as possible," says Jennifer Riesz, a biophysicist at the University of Queensland in Brisbane, Australia. "It does this by very efficiently changing the energy into heat."
But Casadevall and his colleague Ekaterina Dadachova, a nuclear chemist at Einstein, speculate that the melanin in this case acts like a step-down electric transformer, weakening the energy until it is useable by the fungi. "The energy becomes … low [at] a certain point where it can already be used by a fungus as chemical energy," Dadachova argues. "Protection doesn't play a role here. It is real energy conversion."
Cosmos Magazine notes:
Sitting at the centre of the [Chernobyl] exclusion zone, the damaged reactor unit is encased in a steel and cement sarcophagus. It's a deathly tomb that plays host to about 200 tonnes of melted radioactive fuel, and is swarming with radioactive dust.
But it's also the abode of some very hardy fungi which researchers believe aren't just tolerating the severe radiation, but actually harnessing its energy to thrive.
"Our findings suggest that [the fungi] can capture the energy from radiation and transform it into other forms of energy that can be used for growth," said microbiologist Arturo Casadevall from the Albert Einstein College of Medicine at Yeshiva University in New York, USA.
In 1999, a robot sent to map the inside of the reactor returned with samples of a particularly black fungi, indicating an abundance of the biological pigment melanin, which also colours your skin.
Though melanin is typically associated with 'protective' properties – absorbing and safely transforming different electromagnetic wavelengths, such as DNA-damaging ultraviolet light – the researchers had an inkling that a more extraordinary phenomenon was allowing the fungi to prosper; something still involving the combination of melanin and radiation, but beyond the bounds of radioactive protection.
After all, even without melanin, many fungi are intrinsically radiation-resistant.
The group analysed three different types of fungi, including Cladosporium sphaerospermum, the species abundant in and around Chernobyl. Using ionising radiation from the radioactive isotope, caesium-137, they exposed the fungi to radiation doses similar to those inside the damaged reactor, and about 500 times greater than the Earth's normal background level.
Melanin-containing fungi exposed to the radiation – even when nutrient-starved on purpose – grew significantly larger and up to 2.5 times faster than fungi without melanin and those not exposed to radiation.
According to Yeshiva's Ekaterina Dadachova, the nuclear chemist who led the study, "the presence of melanin in the cells gives them a distinct advantage over non-melanised cells, in terms of better growth [with radiation]."
Because the fungi don't actually 'eat' radioactive material, but simply use the energy it radiates, Dadachova said, they're in no danger of becoming radioactive themselves.
Indeed, some bacteria appear to have this property as well. As the Washington Post notes:
At least one of the bacteria species discovered [miles underground] lives entirely disconnected from anything on the Earth’s surface or produced by photosynthesis. It uses the radioactive decay of nearby rocks as the energy source to break apart molecules that it then feeds on.
One of the world's leading authorities on fungi and bioremediation - mycologist Paul Stamets - writes:
Surprisingly, we learned from the Chernobyl disaster some species of melanin-producing fungi thrive, feeding on concrete, within the highly radioactive environment of the damaged containment vessel. At Chernobyl, some fungi’s growth was stimulated by severe radiation, even when exposed to >1,000,000 rads!
Stamets notes that melanin-producing fungi can take radiation out of the environment:
Many people have written me and asked more or less the same question: “What would you do to help heal the Japanese landscape around the failing nuclear reactors?”
Plant native deciduous and conifer trees, along with hyper-accumulating mycorrhizal
mushrooms, particularly Gomphidius glutinosus, Craterellus tubaeformis, and
Laccaria amethystina ... G. glutinosus has been reported to absorb – via the mycelium – and concentrate radioactive Cesium 137 more than 10,000-fold over ambient background levels. Many other mycorrhizal mushroom species also hyper-accumulate.
Continuously remove the mushrooms, which have now concentrated the
radioactivity, particularly Cesium 137, to an incinerator. Burning the mushroom will result in radioactive ash. This ash can be further refined and the resulting
concentrates vitrified (placed into glass) or stored using other state-of-the-art
While Stamets focuses on the area surrounding Fukushima, there is no reason that we can't plant melanin species like Gomphidius glutinosus, Craterellus tubaeformis, and
Laccaria amethystina which are common in areas with pine trees - for example, in many parts of California, Oregon, Washington and Hawaii - to tie up radiation in our soil. Handle them like hazardous waste when you pick and dispose of them (contact your local hazardous waste agency for details).
Indeed, Scientific American notes that regular mushrooms or even plants could be converted into melanin-containing, radiation-loving lifeforms:
Fungi induced to produce a melanin shell (the human pathogen Cryptococcocus neoformans) grew well in such levels of radiation, unlike those sans pigment.
Melanin could be genetically engineered into photosynthetic plants to boost their productivity or melanin-bearing fungi could be used in clothing to shield workers from radiation ...