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Dr. Bin Mori is a professor emeritus at University of Tokyo, Faculty of Agriculture. Since the beginning of the Fukushima nuclear crisis on March 11, the professor has been writing his blog focusing on the effect of radiation in plants and remediation of agricultural land.I have featured his autoradiographs of dandelion and horsetail on my blog before.In his post on October 30, Professor Mori wrote about his discovery, probably the world first, he made in spiders (Nephila clavata) he caught in Iitate-mura, Fukushima Prefecture, where the villagers were forced to evacuate after being designated as "planned evacuation zone". The spiders, he found, had radioactive silver (Ag-110m) at 1,000 times the concentration in the environment.The following is my translation of Dr. Mori's October 30 blog post, with his express permission:

Since it was difficult to collect plants in the rain in Iitate-mura, I caught instead "nephila clavatas" in the bamboo groves and cedar forest.

I don't know whether the spiders eat dirt itself, but I thought they may have concentrated radioactive cesium in their bodies as they were at the top of the food chain in the forest, eating butterflies, horseflies, and drone beetles that they caught in their webs.

Fukushima University researchers plan to measure forest radiation levels in Fukushima Prefecture by placing special monitoring collars on wild monkeys, in light of the nuclear crisis. Each of the collars contains a small radiation meter and a Global Positioning System transmitter, and can be unclipped by remote control. This will allow a team led by robotics professor Takayuki Takahashi to recover the collars and collect the data within one to two months after the monkeys are released back into the wild, they said. Radiation in forests is currently monitored mainly from the air, for example by helicopter, but the researchers believe they can get more detailed data through wild monkeys and aim to implement the project in an area of the city of Minamisoma by spring. The project also is designed to check the radiation exposure of wild animals, they said.

An experiment to test the power of sunflowers to absorb toxic radiation has failed to prove effective near the site of the nuclear disaster at Fukushima, Japan.  The Asahi Shimbun reports that the sunflowers removed only .05 percent of the radioactive cesium in the ground, while the  removal of just over an inch (3 centimeters) of topsoil along with grass removed up to 97 percent of the radioactive cesium. It was hoped that sunflowers would concentrate radioactive waste and could then be removed more easily than the wholesale “scraping” of soil and compost that it seems will  be required. In the meantime scientists are studying ways to decontaminate the forests near the nuclear accident site. According to the Japan Times, the prefecture (county) where the plant is located is 70% forested, and efforts to date have focused on decontaminating urban areas. Removing the contaminated soil and other material from the forest requires such extreme removal methods that the forest’s ecosystem will be seriously damaged.

Whether the radiation is removed by scraping soil or removing plant matter, the radioactive waste still needs to be safely stored. The government has not yet selected a permanent storage site for the tons of soil and debris that needs to be sequestered. Anti-Nuclear Protests Hit Tokyo

The Japanese public’s trust in nuclear power is clearly ebbing, as tens of thousands of citizens took to the streets of Tokyo today (Monday) to protest nuclear power. Police estimated the crowd at 20,000 (while organizers claimed more) as protesters carried signs saying “Sayonara Nuclear Power” to urge the government to eliminate nuclear power from the nation’s energy grid.  Nuclear accounted for 30 percent of Japan’s energy use prior to the Fukushima incident. There have been energy shortages as 30 of the country’s 54 reactors have been taken off line to enable inspections. Large businesses have been asked to take measures to conserve energy, such as adjusting thermostats, varying schedules around peak demand and cutting back on overtime. It has been six months since three of the Fukushima nuclear plant’s six reactors experienced meltdowns following a catastrophic earthquake and tsunami. Surrounding air, soil and water was contaminated and 100,000 residents were forced to evacuate.

Six months after the nuclear meltdowns in Fukushima Prefecture, the public's awareness of the threat posed by radiation is entering a new phase: the realization that the biggest danger now and in the future is from contaminated soil.

The iodine-131 ejected into the sky by the Fukushima No. 1 power station disaster was quickly detected in vegetables and tap water — even as far away as Tokyo, 220 km south of the plant. But contamination levels are now so low they are virtually undetectable, thanks to the short half-life of iodine-131 — eight days — and stepped up filtering by water companies.

But cesium is proving to be a tougher foe. The element's various isotopes have half-lives ranging from two to 30 years, generating concern about the food chain in Fukushima Prefecture, a predominantly agricultural region, as the elements wash fallout into the ground. The root of the problem is, well — roots. Cesium-134 and cesium-137 are viewed as potential health threats because vegetables can absorb the isotopes from the soil they're planted in.

Iitate is located 45km (28 miles) from the Fukushima Dai-ichi nuclear power plant hit by a tsunami on March 11th this year. In the mountains above the town, the forests are turning the colour of autumn. But their beauty is deceptive. Every time a gust of wind blows, Mr Sato says it shakes invisible particles of radioactive caesium off the trees and showers them over the village. Radiation levels in the hills are so high that villagers dare not go near them. Mr Sato cannot bury his father’s bones, which he keeps in an urn in his abandoned farmhouse, because of the dangers of going up the hill to the graveyard.

Iitate had the misfortune to be caught by a wind that carried radioactive particles (including plutonium) much farther than anybody initially expected after the nuclear disaster. Almost all the 6,000 residents have been evacuated, albeit belatedly, because it took the government months to decide that some villages outside a 30km radius of the plant warranted special attention. Now it offers an extreme example of how difficult it will be to recover from the disaster.

That is mainly because of the enormous spread of radiation. Recently the government said it needed to clear about 2,419 square kilometres of contaminated soil—an area larger than greater Tokyo—that received an annual radiation dose of at least five millisieverts, or over 0.5 microsieverts an hour. That covered an area far beyond the official 30km restriction zone (see map). Besides pressure- hosing urban areas, this would involve removing about 5cm of topsoil from local farms as well as all the dead leaves in caesium-laden forests.

The impacts on the ocean of releases of radionuclides from the Fukushima Dai-ichi nuclear power plants remain unclear. However, information has been made public regarding the concentrations of radioactive isotopes of iodine and cesium in ocean water near the discharge point. These data allow us to draw some basic conclusions about the relative levels of radionuclides released which can be compared to prior ocean studies and be used to address dose consequences as discussed by Garnier-Laplace et al. in this journal.(1) The data show peak ocean discharges in early April, one month after the earthquake and a factor of 1000 decrease in the month following. Interestingly, the concentrations through the end of July remain higher than expected implying continued releases from the reactors or other contaminated sources, such as groundwater or coastal sediments. By July, levels of 137Cs are still more than 10 000 times higher than levels measured in 2010 in the coastal waters off Japan. Although some radionuclides are significantly elevated, dose calculations suggest minimal impact on marine biota or humans due to direct exposure in surrounding ocean waters, though considerations for biological uptake and consumption of seafood are discussed and further study is warranted.

there was no large explosive release of core reactor material, so most of the isotopes reported to have spread thus far via atmospheric fallout are primarily the radioactive gases plus fission products such as cesium, which are volatilized at the high temperatures in the reactor core, or during explosions and fires. However, some nonvolatile activation products and fuel rod materials may have been released when the corrosive brines and acidic waters used to cool the reactors interacted with the ruptured fuel rods, carrying radioactive materials into the ground and ocean. The full magnitude of the release has not been well documented, nor is there data on many of the possible isotopes released, but we do have significant information on the concentration of several isotopes of Cs and I in the ocean near the release point which have been publically available since shortly after the accident started.

We present a comparison of selected data made publicly available from a Japanese company and agencies and compare these to prior published radionuclide concentrations in the oceans. The primary sources included TEPCO (Tokyo Electric Power Company), which reported data in regular press releases(3) and are compiled here (Supporting Information Table S1). These TEPCO data were obtained by initially sampling 500 mL surface ocean water from shore and direct counting on high-purity germanium gamma detectors for 15 min at laboratories at the Fukushima Dai-ni NPPs. They reported initially results for 131I (t1/2 = 8.02 days), 134Cs (t1/2 = 2.065 years) and 137Cs (t1/2 = 30.07 years). Data from MEXT (Ministry of Education, Culture, Sports, Science and Technology—Japan) were also released on a public Web site(4) and are based on similar direct counting methods. In general MEXT data were obtained by sampling 2000 mL seawater and direct counting on high-purity germanium gamma detectors for 1 h in a 2 L Marinelli beaker at laboratories in the Japan Atomic Energy Agency. The detection limit of 137Cs measurements are about 20 000 Bq m–3 for TEPCO data and 10 000 Bq m–3 for MEXT data, respectively. These measurements were conducted based on a guideline described by MEXT.(5) Both sources are considered reliable given the common activity ratios and prior studies and expertise evident by several Japanese groups involved in making these measurements. The purpose of these early monitoring activities was out of concern for immediate health effects, and thus were often reported relative to statutory limits adopted by Japanese authorities, and thus not in concentration units (reported as scaling factors above “normal”). Here we convert values from both sources to radionuclide activity units common to prior ocean studies of fallout in the ocean (Bq m–3) for ease of comparison to previously published data.

*Google Translation* Title: Fukushima cesium found in the Finnish woods Source: YLE (Finland Public Television, BBC counterpart) Date: Jan 17, 2012

Finnish forests are small amounts of radioactive cesium, which is derived from Fukushima nuclear power plant in the March accident. Radiation and Nuclear Safety of the cesium-134 and 137 have been found in lichens, fungi as well as elk and reindeer meat. Radioactivity not detected drinking water, milk and food for sale. Radiation collected in late summer and autumn samples, which were found Fukushima cesium. Radiation and Nuclear Safety, the accident caused by the increase in Fukushima Finnish radiation dose is negligible. Fukushima the accident increased the amount of artificial radioactivity in Finnish natural products of the highest per cent. [...]

CHERNOBYL to FUKUSHIMA – Part 3 – A Radiation Biologist’s Story Uploaded by: eon3 Date: Jun 30, 2011 Description: In the third of five parts of a seminar held at San Francisco State University – April 8, 2011, radiation biologist Natalia Manzurova tells of her experience as a Chernobyl ‘clean up liquidator’ – translated by psychologist Tatiana Mukhamedyarova.

Transcript Summary At 5:40 in The dose of radiation exposure was so high that a lot of animals who were exposed to it just went mad… that is they were just… crazy[?] The dogs that were left in the zone went to the forest… foxes, wolves… started attacking people who were working in the zone In fact even the hogs in the wild, they also became mad and also started attacking We were going from Chernobyl where we stayed overnight to Pripyat… one hog attacked our car with such force that we almost went into the ditch in the car

U.S. Senator Lamar Alexander (R-Tenn.), chairman of the Senate Republican Conference, delivered a speech this week at the International V.M. Goldschmidt Conference in Knoxville.  Alexander serves on the Senate Environment and Public Works Committee and is the chairman of the Tennessee Valley Authority Congressional Caucus.  His remarks as prepared follow:

When

in a speech in Oak Ridge in May of 2009, I called for America to build 100 new nuclear plants during the next twenty years.  Nuclear power produces 70 percent of our pollution-free, carbon-free electricity today.  It is the most useful and reliable source of green electricity today because of its tremendous energy density and the small amount of waste that it produces.  And because we are harnessing the heat and energy of the earth itself through the power of the atom, nuclear power is also natural.

When the governor of Fukushima started to say "post-nuke", I thought "OK, he must have found a new way to benefit from the close ties with the national government, other than nuke, or in addition to nuke."According to Yomiuri Shinbun, the latest and final version of the Kan administration's plan for recovery and reconstruction after the March 11 earthquake/tsunami for Fukushima Prefecture will include a host of government research institutions going to Fukushima, with the related industries - heavy electric, utilities, pharmaceutical, etc. - tagging along.

Dr. Shunichi "100 millisieverts are no problem" Yamashita is already in Fukushima, salivating at the unique, world-first opportunity to study the long-term effect of radiation on children. Also, Fukushima University and the Japan Atomic Energy Agency, of Monju fame, have signed an agreement to cooperate in research and development of the world-class decontamination technology, among others. (Links are in Japanese.)That the government research institutions rushing to Fukushima makes me wonder if the whole plan is one gigantic experiment using the land, water, air, people, animals, crops, forests and mountains in Fukushima to develop world-class technologies in radiation medicine and decontamination, and renewable energy that the government and the industries can later capitalize on.

Yomiuri Shinbun (3:03AM JST 7/27/2011)

Up to 28 million cubic meters of soil contaminated by radioactive substances may have to be removed in Fukushima Prefecture, according to the Environment Ministry. In a simulation, the ministry worked out nine patterns according to the rates of exposure to and decontamination of radioactive materials in soil, mainly in forests. The ministry found if all the areas which were exposed to 5 millisieverts or more per year were to be decontaminated, 27.97 million cubic meters of contaminated soil would have to be removed. The calculation covered 13 per cent of the prefecture’s area. These figures indicate the size of the temporary facilities that will be needed to store the soil, and the capacity of intermediate storage facilities where the soil will be taken later. End Extract http://www.asiaone.com/News/Latest%2BNews/Asia/Story/A1Story20110926-301472.html

Japan faces the prospect of removing and disposing 29 million cubic metres of soil contaminated by the world's worst nuclear crisis in 25 years from an area nearly the size of Tokyo, the environment ministry said in the first official estimate of the scope and size of the cleanup. Six months after the March 11 earthquake and tsunami triggered reactor meltdowns, explosions and radiation leaks at Fukushima Daiichi nuclear power plant on Japan's northeast coast, the size of the task of cleaning up is only now becoming clear. Contaminated zones where radiation levels need to be brought down could top 2,400 square km (930 square miles), sprawling over Fukushima and four nearby prefectures, the ministry said in a report released on Tuesday.

If a 5 cm (2-inch) layer of surface soil, likely to contain cesium, is scraped off affected areas, grass and fallen leaves are removed from forests, and dirt and leaves are removed from gutters, it would amount to nearly 29 million cubic metres of radioactive waste, the document showed. This would be is enough to fill 23 baseball stadiums with a capacity of 55,000 spectators, and the government must decide where to temporarily store such waste and how to dispose of it permanently.

Japan has banned people from entering within a 20 km (12 mile) radius of the plant, located about 240 km (150 miles) northeast of Tokyo and owned by Tokyo Electric Power Co . Some 80,000 people were forced to evacuate. The government aims to halve radiation over two years in places contaminated by the crisis, relying on both the natural drop in radiation as time passes and by human efforts.

NGO "FoE Japan (Friends of Earth Japan) did its own survey of radiation contamination in Watari District in Fukushima City with the help from Professor Tomoya Yamauchi of Kobe University. Watari District has high radiation levels throughout the district, but the national government has so far refused to designate anywhere in the district as "evacuation recommended" area.If the government designate an area as such, the government has to pay for the relocation cost. As the result, the designation in other cities like Date City has been very arbitrary and spotty, rendering the whole exercise worthless. Often, the residents are simply moved to the other parts of the same city with slightly lower radiation.

Judging from Professor Yamauchi's air radiation survey (in Japanese), this particular location looks like the one that had 23 microsieverts/hour radiation at 1 centimeter off the surface of the dirt in the roadside drain. Professor Yamauchi hypothesized that radioactive cesium from surrounding mountains and forests washes down the drain after the rain, and naturally gets concentrated in the dirt.

In my communication with Professor Yamauchi, I asked if the decontamination as currently practiced in Fukushima works at all, given the non-result in Watari District which he surveyed. He said the spot decontamination like removing the dirt and sludge is useless as radioactive materials simply come from somewhere else, so the district-wide decontamination including the surrounding mountains would be necessary to "decontaminate" in the true sense of the word - to remove radioactive materials, not reduce.

Kiwamu Ariga skirted the paddies of ripening rice, moving briskly despite his 81 years to reach a pile of yellowish rocks at the foot of a steep, forested hillside.

It was here that, as a junior high school student in the final months of World War II, Mr. Ariga and his classmates were put to work hacking rocks out of the hill’s then exposed stone face until the blood ran from their sandaled feet. The soldiers told them nothing beyond instructing them to look for stones with brown or black spots.

an officer finally explained what they were after: “With the stones that you boys are digging up, we can make a bomb the size of a matchbox that will destroy all of New York.” Mr. Ariga said he did not learn other details of Japan’s secrecy-wrapped efforts to build an atomic bomb until years after the war.

Seiji Maehara, who lost his bid to become the party leader and the prime minister of Japan, has nonetheless landed on a very powerful party position as the chairman of the DPJ's policy bureau.He went to Fukushima, and after visiting with the evacuees from Iitate-mura, he disclosed his party's plan to use the "eco-point" system for residential housing to promote timber from the disaster-affected area.

What is the "eco-point" for houses? Well, if you build or renovate your house with energy saving features and alternative energy features (eg. solar panels) the government will give you "eco-points". Then you can use the points at participating stores and buy whatever you want to buy with the points.Maehara is saying the government may entice builders to use the lumber from the disaster-affected area with "eco-points", even if the potentially radioactive lumber has nothing to do with energy saving.

Iitate-mura's major industry is forestry. Iitate-mura's mountains and forests have been contaminated with whatever fell on them - radioactive cesium, plutonium, strontium. No one has tested them (if someone did, he's not saying anything), but the contamination should be an order of magnitude bigger than the radioactive firewood from Rikuzen Takata City in Iwate Prefecture.

"They scoop up soil from their gardens and dump it in holes dug out in parks and nearby forests, scrub their roofs with soap and refuse to let their children play outside. "More than three months after a massive earthquake and tsunami triggered a nuclear meltdown at a nearby power plant, Fukushima residents are scrambling to cope with contamination on their own in the absence of a long-term plan from the government. " 'Everything and everyone here is paralysed and we feel left on our own, unsure whether it's actually safe for us to stay in the city,' said Akiko Itoh, 42, with her four-year old son in her lap." Reuters

Part of the Radiological Assistance Program (RAP) team, region five, their normal operating ground covers 10 Midwestern states—but this time their expertise was needed abroad. Trained in radiation detection and monitoring, RAP teams are on call twenty-four hours a day to respond to any release of radiological materials in the U.S. When the reactors at Fukushima Daiichi began to emit radioactive material, the Department of Energy’s national emergency response assets, including several RAP teams, responded to calls from both the U.S. Department of State and the U.S. military. They wanted guidelines on protecting U.S. citizens and military personnel stationed in Japan from radiation hazards; but this raised the enormous task of finding out how much radiation had been dispersed.

In late March, several Argonne members flew to Japan to take over shifts from the initial response team members, who had been working around the clock to take measurements at U.S. military bases, other U.S. interests, and elsewhere in the 50-mile radius around the reactors. On the ground, small teams set out to comb the earthquake-stricken countryside, radiation detectors in tow. They took hundreds of readings and collected soil samples, mostly between the 20-80 kilometer zone from the plant. They ran into challenges right away.

"One of the problems we ran into was accessibility," said Dave Chamberlain, an Argonne chemical engineer with RAP. "When you practice going out to get samples, the classic technique is to divide the area into a grid and take samples say, every 10 meters. But many of the areas we were sampling in Japan were mountainous, forested and damaged by earthquakes, so you can't stick to the grid plan. We were often limited to roadside sampling." "The other difficulty was that we wanted samples from ground that hadn't been disturbed since the accident," explained Chamberlain. "If someone had plowed or watered the ground, it changes the dynamics of the distribution—and that time of year is rice planting season in Japan."