As we know, the threat from radiation is a long-term one. Chernobyl continues to have a large exclusion zone almost 30 years after the nuclear accident. 60 years after the nuclear testing that took place there, Bikini Atoll is still uninhabitable. The ambient exposure levels are acceptable, however the soil is still so contaminated that if people lived there and grew food, it would be unsafe to consume. The effects of contamination from Chernobyl are spread far and wide. Even today nuclear contamination from Chernobyl afflicts Turkish agriculture. Dr. Helen Caldicott has stated that the products of Turkish agriculture are still contaminated and should not be consumed.
The primary contaminants of concern are cesium and strontium, both of which are easily absorbed by plants from the environment. Considering these radionuclides will be present in significant quantities for the next 200 years, it would make sense to take an active approach to prevent a situation like what ha Japan’s has a frightening lack of food security. Even before the crisis, Japan only produced 40% of it’s own food domestically. The Japanese farming population is mostly elderly, and any nascent interest in agriculture that might have existed in the younger generation has likely been dimmed significantly by the current disaster. The despair felt by farmers was expressed succinctly and tragically by an organic grower from Fukushima who hanged himself shortly after the nuclear accident.
Contaminated areas in Fukushima, Ibaraki and Chiba prefectures have historically produced a large percentage of the rice and vegetables to feed the metropolis of Tokyo. This entire area has been covered in radionuclides. Only small areas have been banned from production, however, a former nuclear adviser to the Prime Minister has warned of chaos that he believes will ensue once this year’s rice harvest gets underway and the levels of contamination are better understood.
Considering Japan’s precarious food security and the amount of radiation exposure that people have already had, it is imperative that the soils of the Kanto and Tohoku regions undergo a thorough process of decontamination.
The only way to orchestrate a nuclear cleanup on this scale is bioremediation, the use of living organisms to remedy environmental contamination. To date, proposals I have encountered include two major approaches to bioremediation: Mycoremediation and Phytoremediation. Mycoremediation means using various strains of fungi to clean up radionuclides. The primary proponent of this is mycologist and researcher Paul Stamets, author of “Mushrooms Can Save the World”. Phytoremediation uses plants, including sunflowers(helianthus), indian mustard (brassica), and pigweed (amaranthus).
Below are the steps in Paul Stamets’ proposal:
1) Evacuate the region around the reactors.
2) Establish a high-level, diversified remediation team including foresters, mycologists, nuclear and radiation experts, government officials, and citizens.
3) Establish a fenced off Nuclear Forest Recovery Zone.
4) Chip the wood debris from the destroyed buildings and trees and spread throughout areas suffering from high levels of radioactive contamination.
5) Mulch the landscape with the chipped wood debris to a minimum depth of 12-24 inches.
6) Plant native deciduous and conifer trees, along with hyper-accumulating mycorrhizal mushrooms, particularly Gomphidius glutinosus, Craterellus tubaeformis, and Laccaria amethystina (all native to pines). 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.
7) Wait until mushrooms form and then harvest them under Radioactive HAZMAT protocols.
8) Continuously remove the mushrooms, which have now concentrated the radioactivity, particularly Cesium 137, to an incinerator. Burning the mushroom willresult 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 storage technologies.
Stamets’ full proposal can be found here: The Nuclear Forest Recovery Zone Mycoremediation of the Japanese Landscape After Radioactive Fallout by Paul Stamets
Following is an excerpt from an article about phytoremediation. The rest of the article is linked at the bottom of the quote:
Botanical cleanup crews: using plants to tackle polluted water and soil – phytoremediation
by Tina Adler
Rafts with sunflowers growing on them float on a small pond at the Chernobyl nuclear accident site in the Ukraine. No, it’s not some touching monument to the 1986 disaster. The plants are helping to clean the pond; their roots dangle in the water to suck up the radionuclides cesium 137 and strontium 90.
This sunflower project is one of many international efforts at phytoremediation-the use of plants to absorb pollutants from air, water, and soil. In the United States, both government agencies and private companies, including Exxon Corp. and DuPont are testing a variety of plants to see if they can do some of the dirty work of cleaning up such pollutants as radioactive material, lead, selenium, and oil. Many plants, it turns out, have a taste for these stubborn contaminants.
“To survive, plants have evolved sophisticated metabolic and sequestration mechanisms to detoxify a wide variety of chemical substrates,” explains Scott Cunningham of DuPont Central Research and Development in Newark, Del. The plants are also loaded with microbes and fungi that help break down the chemicals. Cunningham spoke in May at a conference on phytoremediation held in Arlington, Va.
The Chernobyl sunflower project began in 1994. That summer, researchers from Phytotech, a phytoremediation company in Monmouth Junction, N.J., and their government and university colleagues installed the rafts. Together, they held 24 sunflowers and dotted a 75-square-meter pond located 1 kilometer from the Chernobyl reactor, says Burt Ensley, Phytotech’s president.
The plants preferentially absorb cesium and strontium from a mixture of metals, he notes. The plants don’t metabolize the radionuclides, but the cesium stays in the roots and most of the strontium moves to the shoots. The company disposes of the plants as radioactive waste after about 3 weeks on the pond.
The investigators started with too few flowers to clean the pond completely, Ensley acknowledges. This summer, they installed 50 to 60 sunflowers, which should clean the pond in a couple of weeks, he asserts. Ensley estimates that removing radioactive metals with sunflowers costs $2 to $6 per thousand gallons of water, much less than existing technologies. However, to avoid recontaminating the pond, the ground nearby must be decontaminated at the same time. For 2 years, Phytotech scientists have been removing cesium and strontium from soil on one-quarter acre of the Chernobyl site by growing Indian mustard (Brassica juncea). In the United States, almost all radioactive sites belong to the Department of Energy. Prior to the Chernobyl sunflower project, Phytotech researchers experimented with pumping contaminated groundwater into containers of sunflowers at a DOE uranium-processing plant in Ashtabula, Ohio. Within 24 hours, the plants reduced the concentration of uranium in the water from 350 parts per billion (ppb) to less than 5 ppb, which meets the legal limits for groundwater, Ensley says.
Read the full article here.
I have heard that grassroots efforts are already underway in Japan to plant sunflowers with this purpose in mind. The current state of paralysis and overwhelm experienced by the Japanese government makes it obvious that any bioremediation efforts are going to need to be spearheaded by private citizens, NGO’s and university research departments. Prefectural governments or TEPCO itself are only likely to get involved in something so proactive once people start leaving piles of radioactive sunflowers at the front door to the offices. I am open to being pleasantly surprised about positive movement from the public sector, however, I don’t suggest that people hold their breath waiting for the government or TEPCO to clean up the mess. It is time for the people to take matters in their own hands and start planting sunflowers and propagating mycorrhizal fungi and decontaminating their own land. The alternatives are for the Japanese people to give up farming in the Kanto and Tohoku regions or eat radiation for the next 100 years.