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Not to the extent that may cause "chaos" as Professor Kosako predicted, but the prefectural authorities have tested the early harvest and radioactive cesium has been found in Ibaraki and Chiba. The first to find radioactive rice was Ibaraki Prefecture, but the governor vows to fight the "baseless rumor" to promote rice from his prefecture. From Sankei Shinbun (8/19/2011):

As the brown rice grown in Hokota City in Ibaraki Prefecture was found with radioactive cesium, Governor of Ibaraki Masaru Hashimoto answered the reporters on August 19 and said "There is no problem with safety. After the formal testing is complete by the end of August, we will persuade the consumers that there's nothing to worry about consuming Ibaraki rice", and that he will do his best to counter the "baseless rumor".

Governor Hashimoto emphasized safety by saying "It is not the level to worry, even if you eat [the rice] for one whole year". At the same time, he said "Since radioactive cesium has been detected in vegetables, I wouldn't have been surprised to see it detected in rice".

The highly radioactive dirt in Kashiwa City in Chiba, which measured 57.5 microsieverts/hr 30 centimeters below the surface, was not from radium after all or any other nuclides that are used in industrial or medical use (some suggested cobalt-60, for example). It was from radioactive cesium.On October 22 Kashiwa City announced the result of the analysis of three dirt samples from the location at different depth (one on the surface, two at 30 centimeter deep). The analysis was done on October 22. The unit is becquerels per kilogram:Sample A (surface dirt)Radioactive iodine: NDCesium-134: 70,200Cesium-137: 85,100Total cesium: 155,300

Sample B1 (30 centimeters below the surface)Radioactive iodine: NDCesium-134: 87,000Cesium-137: 105,000Total cesium: 192,000Sample B2 (30 centimeters below the surface)Radioactive iodine: NDCesium-134: 124,000Cesium-137: 152,000Total cesium: 276,000The address of the location is announced by the city as: 柏市根戸字高野台457番3地先. According to the residents, the place is a strip of open space between the residential area and the industrial area, and is used as playground by many residents, young and old.

On receiving the result of the analysis, the Ministry of Education and Science, who had expressed doubt that this high radiation spot in Kashiwa had anything to do with the Fukushima I Nuclear Power Plant accident, now says it cannot deny that it is the result of the accident. The ratio of cesium-134 and cesium-137 is consistent with the radio from the accident.Some speculate that someone in the city cleaned out his house and dumped the resulting radioactive sludge and dirt in this location.What I find it odd is the mismatch of the radiation on the dirt surface, 57.5 microsieverts/hour, and the density of radioactive cesium, maximum 276,000 becquerels/kilogram. The density is too low to account for the extremely high radiation. Cesium alone may not account for the high radiation, but There's no mention in the city's announcement whether it is going to test for other gamma nuclides not to mention alpha and beta.

*Google Translation* Title: Cesium 9,686 Bq / kg soil in Osaka Bay seabed emergency essentials – 1 / 14, strontium-90 detected! Source: http://dub314.blog.fc2.com Date: Jan 14, 2012 Cesium 9,686 Bq / kg soil in Osaka Bay seabed emergency essentials – 1 / 14, strontium-90 detected! - Kind of analysis [core] MAX 9,686Bq/kg

1 / Bay / Osaka grab bottom sampler, December 29 Kansai International Airport near the seabed soil Cesium 134 7,271Bq／Kg Cesium 137 705Bq／Kg Strontium-90 28Bq／Kg 2 / Bay / Osaka grab bottom sampler, December 29 浜寺, seabed soil near the river mouth of the Yamato Cesium 134 8,924Bq／Kg Cesium 137 762Bq／Kg Strontium-90 31Bq／Kg

3 / Bay / Osaka grab bottom sampler, December 29 An Zhichuan estuary to pay near-bottom soil reel Cesium 134 3,527Bq／Kg Cesium 137 269Bq／Kg Strontium-90 ND (not detected) Tsuna / Awaji Cesium 134 2,590Bq／Kg Cesium 137 172Bq／Kg

Have these numbers changed over time? If so by how much? I went to look for TEPCO's handouts in the past. In Reactor 1 SFP, the amount of radioactive cesium increased in 2 months, while in Reactor 3 SFP it has steadily decreased. In Reactor 4 SFP the amount is about the same (here's the May analysis). In Reactor 2 SFP the amount is also about the same. Spent Fuel Pool 1: 6/24/2011: Cesium-134: 12,000 becquerels/cubic centimeters Cesium-137: 14,000 becquerels/cubic centimeters

8/19/2011: Cesium-134: 23,000 becquerels/cubic centimeters Cesium-137: 18,000 becquerels/cubic centimeters

Spent Fuel Pool 3: 5/8/2011: Cesium-134: 140,000 becquerels/cubic centimeters Cesium-137: 150,000 becquerels/cubic centimeters 7/7/2011: Cesium-134: 94,000 becquerels/cubic centimeters Cesium-137: 110,000 becquerels/cubic centimeters

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.

In one location, the contamination level is more than 10 times the Chernobyl level. What a surprise. Now that PM Kan is out, the government dribbles out the information that it withheld as it de-emphasized and even attacked the reports of high soil contamination as measured by private entities including citizens' groups.

The most contaminated location found so far is Okuma-machi, where Fukushima I Nuke Plant is located: 29,460,000 becquerels per square meter with cesium-134 and cesium-137 combined, 15,450,000 becquerels per square meter if only cesium-137 is counted.

The confiscated/closed zone after the Chernobyl accident is set in locations whose cesium-137 level in soil exceeds 1,480,000 becquerels per square meter. The level of cesium-137 in the location in Okuma-machi is 10 times that of the Chernobyl confiscated/closed zone. From Yomiuri Shinbun (3:05AM JST 8/30/2011):

Ministry of Education, Culture, Sports, Science and Technology quit measuring plutonium but they mistakenly published the contamination map of Tokyo, Kanagawa and north Kanto area. It was measured by a helicopter. Page 3 Radiation level of Tokyo (1m from the ground) Page 4 Cesium 134+137 on the ground in Tokyo Page 5 Cesium 134 on the ground in Tokyo Page 6 Cesium 137 on the ground in Tokyo Page 7 Radiation level of Kanagawa (1m from the ground)

Page 8 Cesium 134+137 on the ground in Kanagawa Page 9 Cesium 134 on the ground in Kanagawa Page 10 Cesium 137 on the ground in Kanagawa Page 11 Radiation level of north kanto (1m from the ground) Page 12 Cesium 134+137 on the ground in north Kanto Page 13 Cesium 134 on the ground in north Kanto Page 14 Cesium 137 on the ground in north Kanto Overview: Gunma, Tochigi, and north Chiba have hot spots. also, Katsushika, Hachioji, and western part of Tokyo are very contaminated.

First it was "it cannot be from Fukushima I Nuke Plant" when the radiation measured was 57.5 microsieverts/hour.Then it was "it may be from Fukushima I Nuke Plant, and it may not be" when the density turned out to be 276,000 becquerels/kg of radioactive cesium. But since the density was very high, the suspicion was voiced all around (including me) that someone secretly dumped the radioactive sludge or dirt, possibly from cleaning out his yard, onto that location.The Ministry's current position: "It is highly likely that radioactive cesium is from Fukushima I Nuke Plant, and radioactive cesium has been condensed at that particular location because the storm drain nearby was broken."So radioactive cesium from Fukushima I Nuke Plant has been naturally concentrated by elements, 200 kilometers away from the plant, to the density level on par with those found in Fukushima. The Kashiwa City's dirt contains almost as much radioactive cesium in the dirt in the location in Watari District (link is in Japanese) in Fukushima City where 300,000 becquerels/kg of radioactive cesium was found (also near the drain).

Points from the Ministry's announcement on October 23, 2011 "Result of the investigation of Kashiwa City's location with high air radiation" (my translation, not the Ministry's):On receiving the result of the soil analysis on October 22 where maximum 276,000 becquerels/kg of radioactive cesium was detected, the Ministry sent two officials, along with three experts from Japan Atomic Energy Agency on October 23 to Kashiwa City to consult with the local officials in charge of radiation countermeasures.The Ministry's survey of the location included measuring air radiation levels at the location and nearby, and investigating the surroundings to figure out what caused the high radiation level.Survey result:Maximum 2.0 microsieverts/hour 1 meter off the groundMaximum 4.5 microsieverts/hour 50 centimeter off the groundMaximum 15 microsieverts/hour on the ground

Typical air radiation levels in the surrounding area at 1 meter off the ground was 0.3 microsievert/hour.A 50-centimeter wide breach was found in the side drain (30-centimeter deep) next to the location with the high air radiation. This breach was close to the spot where cesium-134 (half life 2 years) was detected. We therefore presume that the rainwater containing radioactive cesium that came from the Fukushima I Nuclear Power Plant accident flowed in from the breach in the side drain, and radioactive cesium was condensed and accumulated in the soil at that particular location.Asahi Shinbun (10/23/2011) has the picture of the broken side drain.

Here's the image of the test report by Isotope Research Institute in Yokohama City:Strontium-90: 195 becquerels/kg

From the same sample, cesium-134 and cesium-137 were also detected earlier.Cesium-134: 29,775 becquerels/kgCesium-137: 33,659 becquerels/kgTotal cesium: 63,434 becquerels/kg

Isotope Research Institute didn't start testing for radioactive strontium until August 20, according to the Institute's website. Thus the time lag.At the Institute, it costs 65,000 yen (US$847) (pre-tax) to test one sample for strontium-90 (no separate testing for strontium-89), and it takes one week. No volume discount, the webpage says.The ratio of strontium-90 to cesium-137 in this case is about 0.58%. In comparison, the same ratio from the samples taken in Fukushima Prefecture was between slightly less than 0.1% to 8.2%. In other words, the ratio varies too much to discern any pattern.Yokohama City has said it is testing for strontium in the sample taken from the same apartment rooftop but with much higher cesium density (105,600Bq/kg total cesium). But remember there was no official announcement about this high cesium detection because "the apartment building is a private property", according to the city. We'll see if Yokohama will announce anything about strontium-90.

Kazue Tazaki is a professor emeritus at Kanazawa University in Ishikawa Prefecture. She took the contaminated soil from Iitate-mura in Fukushima Prefecture where the villagers were required to evacuate, and grew rice using that soil.Rice planting and growing was banned in Iitate-mura this year.Professor Tazaki just harvested the rice, and measured the concentration of cesium-137. The result?From the rice grains: 2,600 becquerels/kgFrom the straw: 2,200 becquerels/kgFrom the roots: 1,500 becquerels/kgSoil contamination: 50,000 becquerels/kgRoughly an equal amount of cesium-134 is to be expected. The transfer rate of cesium-137 in this case was about 0.05.

From Toyama Shinbun, local paper in Ishikawa Prefecture (9/27/2011):

Kazue Tazaki, professor emeritus at Kanazawa University has compiled the result of her experiment of growing rice using the soil from Iitate-mura in Fukushima Prefecture where high radiation levels have been recorded. 2,600 becquerels/kg of radioactive cesium was detected from the harvested rice, more than 5 times the provisional safety limit (500 becquerels/kg) set by the national government. It was prohibited to plant rice in Iitate-mura because of the Fukushima I Nuclear Power Plant accident. The professor's data will be extremely valuable in studying the effect of radiation in the soil on the agricultural crops.

While readings of radiation in the air have returned to pre-3/11 levels in most areas of Japan — not including areas close to the plant and the so-called hot spots — the contamination of soil, which affects the food chain, could pose a long-term health risk, experts say. Iodine-131, cesium-134 and cesium-137 were released in large quantities by the nuclear plant, and if they are accumulated in the body, they could cause cancer.

Kunikazu Noguchi, lecturer at Nihon University and an often-quoted expert on radiological protection, assures that consumers need not worry too much about any produce on the market, because at present, radiation levels in most vegetables, meat, dairy and other foods, even those from Fukushima Prefecture, are far below the government's safety limits and often undetectable. But for consumers concerned about the few incidents of tainted food slipping through the government checks (such as the beef from cattle that had been fed with tainted straw in Fukushima, which was shipped nationwide in July), or families with small children, Noguchi suggests a simple way to minimize their radiation exposure through food: rinse it.

rinsing the food well before cooking, preferably with hot water, and/or boiling or stewing it, a large portion of radioactive elements can be removed. In his book, published in Japanese in mid-July, "Hoshano Osen kara Kazoku wo Mamoru Tabekata no Anzen Manyuaru" ("The Safety Manual for Protecting Your Family From Radiation Contamination"), Noguchi offers tips on how to prepare food, item by item, so consumers can reduce their radiation intake at home.

Minamisoma local government has finally published the result of WBC for 2884 elementary and junior high school students. They announce ONLY 274 of them had cesium 137 ,but the result about cesium 134 is concealed. According to their trustworthy report,only 9 students had more than 20 Bq/ kg,but data about cesium 134 is concealed. The worst case was the 8 years old girl. She had Cesium 134 1192Bq Cesium 137 1723Bq Total 2915Bq

No wonder they did not check other radioactive material ,such as strontium or plutonium.

The apartment building is located in the same Kohoku-ku in Yokohama City where 63,000 becquerels/kg of radioactive cesium was found also from the rooftop of another apartment building, and 42,000 becquerels/kg was found from the dirt around the side drain on the road.It looks like this person had the dirt on the rooftop tested on his own, and posted the test result sheet on his blog.Cesium-134: 49,900 becquerels/kgCesium-137: 55,700 becquerels/kgTotal radioactive cesium: 105,600 becquerels/kg

Meanwhile, this is how the Yokohama City workers (or the contract workers) "cleaned" the highly contaminated (42,000 becquerels/kg cesium) dirt from the side of the road. No protection, no masks, no rubber boots.

Yokohama City Assembly recently voted down the citizens' petition asking the city not to accept radiation-contaminated disaster debris from Tohoku by the majority vote by the DPJ and LDP and Komei Party.The city temporarily halted the dumping of radioactive sludge ashes into the ocean as the citizens' protests were fast and furious once they knew about the scheme, but the mayor in the press conference took pains to emphasize that only thing that had gone amiss was that the city officials under her clearly didn't "explain" well enough to the Yokohama residents living in the area around the final dumping site in Minami Honmoku Pier in advance. "We should have explained better to soothe the fear and anxiety of the residents", she said.

Radioactive substances from the crippled Fukushima No. 1 nuclear power plant have now been confirmed in all prefectures, including Uruma, Okinawa Prefecture, about 1,700 kilometers from the plant, according to the science ministry. The ministry said it concluded the radioactive substances came from the stricken nuclear plant because, in all cases, they contained cesium-134, which has short half-life of two years. Before the March 11 Great East Japan Earthquake, radioactive substance were barely detectable in most areas.

the Ministry of Education, Culture, Sports, Science and Technology's survey results released on Nov. 25 showed that fallout from the Fukushima plant has spread across Japan. The survey covered the cumulative densities of radioactive substances in dust that fell into receptacles during the four months from March through June. Figures were not available for Miyagi and Fukushima prefectures, where the measurement equipment was rendered inoperable by the March 11 disaster. One measurement station was used for each of the other 45 prefectures. The highest combined cumulative density of radioactive cesium-134 and cesium-137 was found in Hitachinaka, Ibaraki Prefecture, at 40,801 becquerels per square meter. That was followed by 22,570 becquerels per square meter in Yamagata, the capital of Yamagata Prefecture, and 17,354 becquerels per square meter in Tokyo's Shinjuku Ward.

The current air radiation level in Ibaraki Prefecture is about 0.14 microsievert per hour, equivalent to an annual dose of about 1 millisievert, the safety limit for exposure under normal time international standards. Large amounts of radioactive dust fell in Tokyo, but a separate survey has detected relatively low accumulations of cesium in the soil. "Tokyo has smaller soil surfaces than other prefectures, but road and concrete surfaces are less prone to fixate cesium deposits, which were probably diffused by the wind and rain," a ministry official explained.

"It's not food any more, it's simply radioactive materials", as the young man at the Citizen's Radioactivity Measuring Station in Fukushima City said of the radioactive mushroom in Germany's ZDF program aired on August 9. Wild mushroom harvested in a town in Fukushima tested highest ever radioactive cesium so far in food after the Fukushima I Nuke Plant accident that I'm aware of: 28,000 becquerels per kilogram.

According to the data from Fukushima Prefecture, 13,000 becquerels/kg of cesium-134, and 15,000 becquerels/kg of cesium-137 were detected from the mushroom. The town, Tanakura-machi, is located at about 73 kilometers southwest of Fukushima I Nuclear Power Plant. From Yomiuri Shinbun (9/3/2011):

Fukushima Prefecture announced on September 3 that 28,000 becquerels/kg of radioactive cesium was detected from wild mushroom, Lactarius volemus, harvested in the mountains in Tanakura-machi. The level of radioactive cesium vastly exceeds the national provisional safety limit of 500 becquerels/kg.

SOURCE: Tokyo Metropolitan Government Measures Soil Contamination in Shinjuku, EX-SKF, October 7, 2011

[...] according to the just released Ministry of Education’s aerial survey [...] most of Tokyo has less than 10,000 becquerels/square meter of radioactive cesium, with the exception of the western-most Okutama and the eastern special wards (“ku”) [...] the Tokyo Metropolitan government [...] was doing its annual survey of soil contamination in Shinjuku and quietly released the data on September 20. The soil sample was taken at Tokyo Metropolitan Institute of Public Health in Hyakunin-cho, Shinjuku-ku [...] from the surface to 5 centimeters deep [...]: Iodine-131: ND Cesium-134: 360 becquerels/kg Cesium-137: 430 becquerels/kg Total cesium: 790 becquerels/kg To convert from “per kilogram” to “per square meter”, Japan’s Nuclear Safety Commission uses the factor of 65. The total cesium per square meter in Shinjuku therefore is: 51,350 becquerels per square meter.

730,000 becquerels/kg of cesium-134, and 870,000 becquerels/kg of cesium-137 from the ocean soil in front of the water intake for Reactors 1 through 4, south side.The north side is also high, with 640,000 becquerels/kg of cesium-134 and 760,000 becquerels/kg of cesium-137 (total 1.4 million becquerels/kg of radioactive cesium).They must have analyzed for other nuclides but they are not saying yet.

*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. [...]

Title: UCB Milk Sampling Results Source: University of California Berkeley Department of Nuclear Engineering Date: 1/14/2012 (9:40am)

By integrating all of the milk data we have collected since March 11, we can estimate the total effective dose equivalent (TEDE) one could have received from exposure to fission product isotopes in milk to date. For someone drinking milk at the relatively high rate of one gallon per week, the TEDE could be nearly 1 microsievert, or the total effective dose equivalent for only 12 minutes on an airplane flight or 3.7 hours of the average person’s background exposure from natural sources of radiation.

Pasteurized, Homogenized Milk from the San Francisco Bay Area with Best By Date of 12/29/2011 Cs-134: 0.068 Becquerels/liter (Bq/l) ±0.011 [MDA=0.044] Cs-137: 0.075 Bq/l ±0.015 [MDA=0.052] Total cesium is .143 Bq/l, or 3.87 picocuries/l (pCi/l) (1 Bq = 27.1 pCi). The EPA Maximum Contaminant Level for radioactive cesium in milk is 3 pCi/l:

Japan Agency for Marine-Earth Science and Technology announced that in April, Cesium from Fukushima dropped from air to the pacific ocean and fell down deep in the sea attached to dead plankton. 4/18~4/30, Japan Agency for Marine-Earth Science and Technology measured cesium from particles which is made of dead plankton or sand, smaller than 1mm, called “Marine snow”. It was off shore of Polustrov Kamchatka, where is 2,000 km away from Fukushima and 5,000 meters deep in the sea around Ogasawara islands, where is 1,000 km away from Fukushima. From the ratio of cesium 134 and 137, they judged it was from Fukushima plants. They have not announced the amount of cesium. (Source)