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"Fukushima shiitake cesium spikes Kyodo FUKUSHIMA - Radioactive cesium exceeding the designated limit has been detected in shiitake grown in greenhouses at a farm in Soma, Fukushima Prefecture, the prefectural government said. The prefecture said Saturday it has asked the city of Soma and dealers to stop shipment of the mushrooms, and a local agricultural cooperative has begun recalling them after they were found to contain 850 becquerels of cesium per kilogram, exceeding the 500-becquerel limit set by the state. The farm in question has grown the mushrooms on beds made of a mixture of wood chips and nutrients, and the wood chips used in them are suspected to have been contaminated with the radioactive substance, according to the local government. The mushroom beds were sold by the Soma agricultural cooperative. The farm has shipped 1,070 100-gram packages of shiitake since Oct. 24, and they are believed to have been sold at nine supermarkets in the prefecture from Tuesday. No other shiitake produced by the farm have entered the market, it said."

""The estimated source terms for iodine-131 are very constant, namely 1.3 x 10^17 becquerels per day for the first two days (US station) and 1.2 x 10^17 becquerels per day for the third day (Japan)," the institute said in a German-language statement posted on Wednesday on its website. "For cesium-137 measurements, (the US station) measured 5 x 10^15 becquerels, close, while Japan had much more cesium in its air. On this day, we estimate a source term of about 4 x 10^16." A "becquerel" is the unit that measures how many radioactive nuclei decay per second, and the "source term" refers to the quantity and type of radioactive material released into an environment. "The nuclear catastrophe at Chernobyl had a source term of iodine-131 at 1.76 x 10^18 becquerels of cesium-137 at 8.5 x 10^16 bequerels," the statement added. "The estimated for Fukushima source terms are thus at 20 percent of Chernobyl for iodine, and 20-60 percent of Chernobyl for cesium.""

"Cesium that has fallen and been disturbed from the ground surface- 10 times more internal exposure compared to direct inhalation - JAEA Analysis Japan Atomic Energy Agency [JAEA] (Toukai Village, Ibaragi Prefecture) compiled analyses showing that the amount of internal exposure to radioactive Cesium from particles that had landed on the ground once and then been disturbed and re-floated was 10 times larger than that of inhaling the airborne particles directly. [This study] will be presented on September 22nd at the Japan Atomic Power Conference that's presently being held in Kitakyushuu City. The JAEA Safety Research Center's research fellow Kimura Masanori (Radiological Protection) points out that "an emphasis needs to be placed to prevent re-floating from the ground surface". Using the survey data of TEPCO and the Ministry of Education, Culture, Sports, Science, and Technology collected in Minamisouma City, Fukushima Prefecture, the amounts of internal exposure to Iodine-131, Cesium-134 and Cesium-137 caused by airborne particles (March 20-May 19) and that of re-floated particles (April 3-June 4) were calculated."

"An extensive area of more than 8,000 square kilometers has accumulated cesium 137 levels of 30,000 becquerels per square meter or more after the accident at the Fukushima No. 1 nuclear power plant, according to Asahi Shimbun estimates. The affected area is one-18th of about 145,000 square kilometers contaminated with cesium 137 levels of 37,000 becquerels per square meter or more following the 1986 Chernobyl accident in the former Soviet Union. The contaminated area includes about 6,000 square kilometers in Fukushima Prefecture, or nearly half of the prefecture. Fukushima Prefecture, the third largest in Japan, covers 13,782 square kilometers. The government has not disclosed the size of the area contaminated with cesium 137 released from the crippled Fukushima No. 1 plant. cesium 137 has a long half-life of about 30 years. The Asahi Shimbun calculated the size of the contaminated area based on a distribution map of accumulated cesium 137 levels measured from aircraft, which was released by the science ministry on Sept. 8. "

"A group of Japanese researchers say that a total of 15,000 terabecquerels of radioactive substances is estimated to have been released from the crippled Fukushima Daiichi nuclear power plant into the sea. Researchers at the Japan Atomic Energy Agency, Kyoto University and other institutes made the calculation of radioactivity released from late March through April. The combined amount of iodine-131 and cesium-137 is more than triple the figure of 4,720 terabecquerels earlier estimated by Tokyo Electric Power Company, the plant operator. The utility only calculated the radioactivity from substances released from the plant into the sea in April and May. The researchers say the estimated amount of radioactivity includes a large amount that was first released into the air but entered the sea after coming down in the rain. They say they need to determine the total amount of radioactivity released from the crippled Fukushima Daiichi plant in order to accurately assess the impact of the disaster on the sea."

The first comprehensive survey of soil contamination from the Fukushima Daiichi nuclear plant showed that 33 locations spread over a wide area have been contaminated with long-lasting radioactive cesium, complicating Japan's effort to clean up the disaster-hit region, the government said Tuesday. The survey of 2,200 locations within a 100-km radius of the crippled plant found that those 33 locations had cesium-137 in excess of 1.48 million becquerels per square meter, the level set by the Soviet Union for forced resettlement after the 1986 Chernobyl disaster. Another 132 locations had combined amount of cesium 137/134 over 555,000 becquerels per square meter, the level at which the Soviet authorities called for voluntary evacuation and imposed a ban on farming.

U.S. reactors have generated about 65,000 metric tons of spent fuel, of which 75 percent is stored in pools, according to Nuclear Energy Institute data. Spent fuel rods give off about 1 million rems (10,00Sv) of radiation per hour at a distance of one foot - enough radiation to kill people in a matter of seconds. There are more than 30 million such rods in U.S. spent fuel pools. No other nation has generated this much radioactivity from either nuclear power or nuclear weapons production. Nearly 40 percent of the radioactivity in U.S. spent fuel is cesium-137 (4.5 billion curies) - roughly 20 times more than released from all atmospheric nuclear weapons tests. U.S. spent pools hold about 15-30 times more cesium-137 than the Chernobyl accident released. For instance, the pool at the Vermont Yankee reactor, a BWR Mark I, currently holds nearly three times the amount of spent fuel stored at Dai-Ichi's crippled Unit 4 reactor. The Vermont Yankee reactor also holds about seven percent more rad

"Revelations that radiation-contaminated rice straw used as feed for beef cattle was produced far away from the crippled Fukushima No. 1 Nuclear Power Plant have sent shockwaves through the livestock farming community in Fukushima Prefecture. Consumers have also been filled with a sense of growing distrust in the government over delays in responding to the problem of radiation-tainted beef. Forty-two beef cows that ate rice straw contaminated with radioactive cesium were found to have been shipped from a livestock farm in the Fukushima Prefecture town of Asakawa from April 8. The rice straw had been supplied by a farmer in Shirakawa, about 75 kilometers away from the tsunami-hit nuclear power station."

"Radiation is expected to continue spewing for months from Japan's Fukushima Daiichi nuclear power plant that suffered a meltdown following an earthquake and tsunami in March, but despite grim reports from Japan, the US Environmental Protection Agency (EPA) has quietly stopped running extra tests for radioactive material in America's milk, rain and drinking water. The EPA initially ramped up nationwide testing in the weeks following the disaster in Japan, and radioactive materials like cesium and iodine-131 were detected on US soil. Citing declining levels of radiation, the EPA has abandoned the extra tests, even as reports from Japan indicate that the Fukushima plant continues to emit radiation and the disaster is one of the worst in world history."

"High levels of radioactive cesium have been detected in incinerated ashes at waste disposal facilities in Kashiwa, Chiba Prefecture, in apparent effects from the nuclear crisis at the Fukushima Daiichi power plant, the local municipal office said Monday. At one waste disposal center in Kashiwa, up to 70,800 becquerels of radioactive cesium per kilogram were detected from ashes collected on June 24 and more than 60,000 becquerels were observed from ashes collected on July 1 and 2, the city office said. Up to 48,900 becquerels of radioactive cesium were also detected at a facility for burying the ashes from waste disposal centers in the city, while a maximum of 9,780 becquerels were observed at another waste disposal center, the office said. The figures far exceed the 8,000-becquerel per kilogram cap set by the state for waste disposal facilities to temporarily store such ashes. "

"Radioactive cesium far exceeding the legal limit has been detected in hay that was fed to cattle at a farm in Fukushima Prefecture. The prefecture has been investigating why the cattle were contaminated with the radioactive substance. On Sunday, officials took samples of feed and well water at the farm located in Minamisoma City within the planned evacuation zone. They say 75,000 becquerels per kilogram of cesium has been detected in the feed. This far exceeds the government's safety limit of 300 becquerels per kilogram. The farmer says the cattle had been kept inside but were fed with hay left outdoors after the March nuclear accident. Eleven cattle from the farm were sent to Tokyo to be slaughtered. The beef from the animals contained levels of cesium that were more than triple the legal limit. The prefecture has asked farmers in the city to suspend beef cattle shipments. Fukushima Prefecture will continue to investigate the feed and water and check if there were any problems with the way the cattle were raised."

"According to Japanese news sources, Japanese whalers tested 6 of 17 whales captured 650 kilometers north-east of the Fukushima nuclear reactor. Of the 6 whales tested 2 were found to contain cesium radiation which must have come from the Fukushima nuclear reactor. The first whale contained 31 becquerels per kilogram of cesium radiation and the second whale and the 24.3 becquerels of radioactive cesium per kilogram. Japan Finds Nuclear Radiation In Whales Caught 650 KM From Fukushima Tokyo - Radioactive caesium was detected from two minke whales caught off a city on the northern Japanese island of Hokkaido, 650 kilometres north-east of a damaged nuclear plant, a news report said on Tuesday. Researchers examined six of the 17 whales during so-called research whaling in Kushiro city, which started this year's season in late April, and they detected 31 becquerels and 24.3 becquerels of radioactive caesium per kilogram in the two whales out of the six, Kyodo News reported citing a whalers' association."

"The levels of radiation accumulated in soil near the crippled nuclear power plant in northeastern Japan far exceeded the level of radiation the then-Soviet Union had used as a criterion for urging people to evacuate at the time of the 1986 Chernobyl nuclear disaster, threatening to plague local residents for a lengthy period. Using aircraft, the Ministry of Education, Culture, Sports, Science and Technology checked the cesium-137 (half life of about 30 years) and cesium-134 (half life of about two years) accumulated in soil in collaboration with the U.S. Department of Energy in April. cesium-137 that has longer effects, ranging from 3 million to 14.7 million becquerels per square meter, was detected in Namie, Futaba, Minamisoma, Iitate and Katsurao, northwest of the Fukushima No. 1 Nuclear Power Plant, in Fukushima Prefecture. The levels far exceeded 550,000 bacquerels per square meter, the level the then-Soviet Union had used as a criterion for urging people to evacuate at the time of the 1986 Chernobyl nuclear disaster. Based on recommendations from the International Commission on Radiological Protection (ICRP), the Japanese government used 20 millisieverts per year of radiation in the atmosphere as the criterion to designate evacuation areas in the wake of the nuclear accident in Fukushima. Therefore, there are areas that have not been designated as evacuation zones although they have larger amounts of accumulated radiation. The Ministry of Education, Culture, Sports, Science and Technology says, "Radioactive substances in soil do not enter human bodies immediately." On the other hand, when authorities try to decide whether to allow local residents to return to their homes or resume farming, levels of soil contamination could be one of the hot topics of debate."

" radioactive substance exceeding the state limit has been detected in pasture grass and vegetables in Tochigi and Ibaraki prefectures, neighboring Fukushima Prefecture. 3,480 becquerels of radioactive cesium were detected in one kilogram of pasture grass collected on May 5th in Nikko City, Tochigi Prefecture. The figure exceeds the state limit of 300 becquerels. Also, at two different locations in Nasushiobara City, 3,600 becquerels and 860 becquerels of radioactive cesium respectively were detected in one kilogram of pasture grass collected on May 3rd. Tochigi Prefecture requested farmers in the area where the radioactive substance was detected not to feed pasture grass to livestock. 1,110 becquerels of radioactive cesium were detected in one kilogram of parsley harvested in Ibaraki Prefecture. The figure is more than double the state limit. The parsley had been shipped to a fresh food market in Niigata Prefecture, west of Fukushima. Niigata prefectural government instructed wholesale distributers to stop selling the parsley. Friday, May 13, 2011 05:21 +0900 (JST)"

"The total area contaminated with radiation from the Fukushima No. 1 nuclear power plant is estimated at about 800 square kilometers, or about 40 percent the size of Tokyo, according to a radiation map created by the science ministry and U.S. Department of Energy. The report uses the same level of contamination (555,000 becquerels or higher of cesium-137) that was used to issue compulsory evacuation orders in the Chernobyl nuclear accident in 1986. To determine whether the current evacuation zone is appropriate or when residents can return home, the Nuclear Safety Commission of Japan plans to set up focal sites to heighten its monitoring of the possible further spread of radioactive contamination. "

The accumulated radiation level in Namie, 30 kilometers from the crippled Fukushima Daiichi nuclear power plant, in the three weeks through Friday stood at 17,010 microsieverts, according to a tally released by the science ministry Saturday. The accumulated levels during the period starting March 23 stood at 9,850 microsieverts in Iitate and 495 microsieverts in Minamisoma, both near the plant, it said. The readings compare with the level of 1,000 microsieverts that ordinary people in Japan can expect to be exposed to over one year. The amount of radioactive cesium stood between 12.7 and 71.0 becquerels per liter of surface seawater near the plant on Monday and Wednesday and 10.1 becquerels at deeper levels on Monday, the Ministry of Education, Culture, Sports, Science and Technology said.

-With no end in sight to the crisis at the Fukushima Daiichi nuclear power plant, Japan's neighbors are increasingly stepping up efforts to curb food imports, both fresh and processed, from parts of Japan. South Korea has temporarily banned vegetables from Fukushima and four other prefectures. In addition, the Seoul government on Thursday announced a new measure that calls for government-issued documents for all food products -- mostly processed foods -- from Tokyo, Miyagi and six other prefectures certifying safe levels of radioactive iodine and cesium. The new requirement takes effect May 1. South Korea is also requesting that products from 34 other prefectures be accompanied by documents identifying their origin. As the Japanese have yet to decide whether to accede to the request, importation of such familiar Japanese products as sake rice wine, snacks and cooking sauces, is expected, in effect, to come to a halt starting next week. Another neighbor, Taiwan, has also prohibited food imports from five prefectures, including Fukushima. In addition, all fresh produce and some processed foods from Japan must be tested for radioactivity when they arrive.

Some of the spent nuclear fuel rods stored in the No. 4 reactor building of the crisis-hit Fukushima Daiichi power plant were confirmed to be damaged, but most of them are believed to be in sound condition, plant operator Tokyo Electric Power Co. said Wednesday. The firm known as TEPCO said its analysis of a 400-milliliter water sample taken Tuesday from the No. 4 unit's spent nuclear fuel pool revealed the damage to some fuel rods in such a pool for the first time, as it detected higher-than-usual levels of radioactive iodine-131, cesium-134 and cesium-137. The No. 4 reactor, halted for a regular inspection before last month's earthquake and tsunami disaster, had all of its 1,331 spent fuel rods and 204 unused fuel rods stored in the pool for the maintenance work and the fuel was feared to have sustained damage from overheating. The cooling period for 548 of the 1,331 rods was shorter than that for others and the volume of decay heat emitted from the fuel in the No. 4 unit pool is larger compared with pools at other reactor buildings. According to TEPCO, radioactive iodine-131 amounting to 220 becquerels per cubic centimeter, cesium-134 of 88 becquerels and cesium-137 of 93 becquerels were detected in the pool water. Those substances are generated by nuclear fission. The government's Nuclear and Industrial Safety Agency said the confirmed radioactive materials were up to 100,000 times higher than normal but that the higher readings may have also been caused by the pouring of rainwater containing much radioactivity or particles of radiation-emitting rubble in the pool.

Spinach with radioactive iodine 27 times more than the government-regulated limit was found in the city of Hitachi in Ibaraki Prefecture, more than 100 kilometers south of the crippled Fukushima Daiichi nuclear power plant, but the radiation levels do not affect human health, local authorities said Sunday. The growing public concern over the safety of farm products prompted the government the same day to consider instructing local authorities to halt the shipment of relevant produce within a prefecture if produce made there is found containing radioactive substances at levels exceeding regulation, government sources said. Currently, prefectural governments decide whether to ask municipalities to voluntarily halt shipment of contaminated products. In 1 kilogram of spinach grown in open air in the city, 54,000 becquerels of iodine was detected, exceeding the 2,000 becquerel limit preliminarily set by the government under the food sanitation law, the Ibaraki prefectural government said. The level of cesium in the spinach grown in the city was also higher at 1,931 becquerels, compared to the limit of 500 becquerels.

"In a letter dated May 20, the Nuclear Regulatory Commission's Petition Review Board denied a request by Rep. Paul Hodes, D-N.H., that it order Entergy to keep its Vermont Yankee nuclear power plant off-line until a number of actions have been completed regarding a recent leak of contaminants into the groundwater under the site. Hodes had asked the NRC to prevent Yankee from restarting after its current refueling outage until the removal of tritiated water from the ground is completed. He also asked that Entergy finish removing soil that was contaminated with radioactive cesium, manganese, cobalt, zinc and strontium before the plant is restarted. In addition, Hodes requested that the root cause analysis, the final report on why tritium leaked from the plant, and the NRC's review of documents submitted to it are both completed prior to restart. "