Japan earthquake - contamination & consequences outside Fukushima NPP

In summary, the French IRSN just released a new report concerning the estimated contamination around DAICHI, i extract this map for the Cs contamination based on SPEEDI/MEXT estimations. The complete report is here (french): http://www.irsn.fr/FR/Actualites_presse/Actualites/Documents/IRSN_Rapport_Evaluation_Dosimetrique_Fukushima_16052011.pdf
  • #456
zapperzero said:
Thank you for the link. The internal exposures of the residents (at least of those found to have had large external exposure) should not be up for debate. There are ways to measure it.

Of course you're right. The prefecture's residents' internal contamination is being measured, and until the results are released, there will be debate. And long after as well. I think the 10 people found with more than 10mSv will be prioritized for internal measurements.

Azby
 
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  • #457
"There are ways to measure it." ? If a person had 1 mSv of internal contamination over only one day in March, with a short-lived radioelement like Iodine, can we find this out in a medical check performed as late as today ?
 
  • #458
tsutsuji said:
"There are ways to measure it." ? If a person had 1 mSv of internal contamination over only one day in March, with a short-lived radioelement like Iodine, can we find this out in a medical check performed as late as today ?

I think we all agree that internal contamination measurements weren't carried out soon enough, and the lack of whole-body counters in the area is just another indication of how unprepared the authorities were for this kind of accident. So now we can only extrapolate possible internal contamination ranges for iodine based on reconstructed external exposures, which won't be accurate enough to satisfy anybody. We'll have a much clearer idea for Cs as more results come in.
 
  • #459
tsutsuji said:
"There are ways to measure it." ? If a person had 1 mSv of internal contamination over only one day in March, with a short-lived radioelement like Iodine, can we find this out in a medical check performed as late as today ?

Surely no-one managed to only get contaminated internally with Iodine? Other nuclides are longer-lived.
 
  • #460
zapperzero said:
Surely no-one managed to only get contaminated internally with Iodine? Other nuclides are longer-lived.

Yes, but as the emitted clouds didn't have a constant composition it is hard to tell what could the people be exposed to several month sago. I don't see how you can give a reasonable estimate of the exposure in March or April using todays results.

That's not to say todays screening doesn't make sense, let's just remember it tells only part of the story.
 
  • #461
Borek said:
Yes, but as the emitted clouds didn't have a constant composition it is hard to tell what could the people be exposed to several months ago. I don't see how you can give a reasonable estimate of the exposure in March or April using today's results.

Yet another example of the J-gov acting like the Three Monkeys.
 
  • #462
zapperzero said:
Yet another example of the J-gov acting like the Three Monkeys.

It gets better. Way better. Via ex-skf.

There have been several leaks of water contaminated with radioactive materials from Fukushima I Nuclear Power Plant. Tokyo Shinbun has found out through own investigation that the Nuclear and Industrial Safety Agency under the Ministry of Economy, Trade and Industry has treated the amount of the leaks as "zero" from a legal [or regulatory] point of view, because it was a "state of emergency". The Agency has said it will treat the future leaks and deliberate discharges into the ocean the same way.

...

(I'm sorry, but that's simply so much crap that I have no idea on how to react to that...)
 
  • #463
http://www3.nhk.or.jp/news/genpatsu-fukushima/20111216/0430_josen.html A government working team, investigating the consequences on human health of low radiation doses, announced its conclusions in a 15 December report recommending to bring radiations to 10 mSv/year over the next two years, although there is no clear increase of human health risks for 20 mSv/year doses. In a second step, radiations should be brought to 5 mSv/year, and in the long term, to 1 mSv/year. Concerning children, the criteria for reopening a school in the evacuation zone is an external exposure of 1 μSv/hour or below, and the continuous measurement of internal contamination must be studied.

Decontamination:
http://www3.nhk.or.jp/news/genpatsu-fukushima/20111216/2050_guide.html The Ministry of environment's Guideline for decontamination was explained on 16 December at a meeting in Fukushima city gathering 140 people in charge in local governments in Fukushima prefecture. They asked technical questions about radiation measurement scope and frequency, pressure washing and surface removal of streets, etc. Similar explanation sessions will be conducted in the whole Tohoku region, such as in Sendai city. The Ministry wants to further improve the guideline when the result data of the model operations will become known and with the input of local governments. A Fukushima city official commented that while it is good to use a unified standard, the effectiveness of the measures and some questions concerning costs are still unclear.

Decontamination Guideline (version 1) December 2011 (Japanese):
http://www.env.go.jp/jishin/rmp/attach/josen-gl00_ver1.pdf [Broken] Foreword
http://www.env.go.jp/jishin/rmp/attach/josen-gl01_ver1.pdf [Broken] Assessment of contamination and measuring methods
http://www.env.go.jp/jishin/rmp/attach/josen-gl02_ver1.pdf [Broken] Decontamination process
http://www.env.go.jp/jishin/rmp/attach/josen-gl03_ver1.pdf [Broken] Contaminated Earth collection and transportation
http://www.env.go.jp/jishin/rmp/attach/josen-gl04_ver1.pdf [Broken] Contaminated Earth storage

http://www.env.go.jp/jishin/rmp/conf/03-mat3.pdf This is part of a series of documents from the 3rd meeting of the environment recovery committee. On page 4/6 there are two diagrams. The first one is a "managed final disposal site". The second one is a "shielded final disposal site".

http://www.env.go.jp/jishin/rmp/conf/03-mat2.pdf On page 4/125 there is a diagram of a temporary storage site (about 3 years). On page 7/125 it is a diagram of middle-term storage site (maximum 30 years).

http://mdn.mainichi.jp/mdnnews/news/20111129p2a00m0na010000c.html [Broken] "In areas where the air dosage of radiation is higher than that level [2.5 μSv/hour] and in areas designated as evacuation zones near the crippled Fukushima nuclear plant, however, businesses must ensure each worker carries a dosimeter".

http://mdn.mainichi.jp/mdnnews/news/20111216p2g00m0dm026000c.html [Broken] (English) "GSDF nearly completes cleanup at Fukushima municipal gov't offices"

Food:
http://www.maff.go.jp/e/quake/press_111209-1.html List of food restrictions, updated 9 December (English)
http://www.jfa.maff.go.jp/e/inspection/pdf/111212_kekka_en.pdf Compilation of fisheries products monitoring results. (12 December press release, English) with map and map (distant water)

Rice:
http://wwwcms.pref.fukushima.jp/pcp...ECT&NEXT_DISPLAY_ID=U000004&CONTENTS_ID=26517 This is the page on Fukushima prefecture website where the latest rice "emergency monitoring" results are published. The last one was issued on 16 December : http://wwwcms.pref.fukushima.jp/download/1/suiden_kinkyu_1216.pdf says 1) that 204 additional bags in 4 already tested farms in former Oguni village, Fukushima city were found below the provisional safety level. So far, 15 farms (263 bags) have been found above provisional safety level in Oguni. 2) that 2209 more bags in 2150 farms in Fukushima city, Date, Nihonmatsu and Motomiya's special evacuation zones were tested, finding 1 bag above level in Fukushima city. So far, 9 bags among 3961 tested have been found above level in different villages in those zones (actually only Fukushima city and Date). 3) In Nihonmatsu, former Shibukawa village, one farm had been found above level in an already announced result. The production figures for that farm are revised. 185 more bags in 185 more farms were tested in former Shibukawa village, but all were found below the provisional safety level.

http://www.japantimes.co.jp/text/nn20111209n1.html (English) 9 December article about the Shibukawa contaminated rice.

Fukushima:
http://www3.nhk.or.jp/news/genpatsu-fukushima/20111130/0430_hanmei.html A study by Nagasaki university found that among 170 Nagasaki prefecture citizens, such as medical professionals, who went to Fukushima prefecture after the accident, 55 people, or 32% were detected as having iodine internal contamination in whole body counter tests performed during the first month after the accident. The highest thyroid equivalent dose was 15 mSv. A trend emerges of higher doses being detected among the people who were in Fukushima prefecture during the first week of the accident. As iodine was never detected in the tests performed in June or later among Fukushima citizens, this Nagasaki university study is deemed a valuable document that might be helpful to accurately estimate the doses received by Fukushima prefecture citizens.

http://www3.nhk.or.jp/news/genpatsu-fukushima/20111210/index.html While only a tiny number of citizens have received their personal estimate of external exposure, the Fukushima prefecture is releasing 18 model cases of contamination. One of them is the case of a Kawauchimura inhabitant, staying in the highest radioactive place until 13 March, when he moves to the primary school as a refugee, and further moves to Koriyama city 3 days later : his accumulated dose for 4 months is 0.7 mSv. Another case is that of an Iitatemura inhabitant, staying there until 21 June (date when Iitatemura village office moves to Fukushima city). His accumulated dose is 19 mSv [over 4 months too, probably]. In his case, his yearly dose may well exceed the 20 mSv/year limit. The early governement response, such as information sharing, is being questioned again by those results.

http://www.bloomberg.com/news/2011-12-06/voluntary-evacuees-around-fukushima-plant-may-be-compensated-1-.html [Broken] (English) "Tepco may have to pay (...) compensation to those affected by the disaster, which displaced 160,000 people, (...) said a government panel"

http://mdn.mainichi.jp/mdnnews/news/20111126p2a00m0na016000c.html [Broken] (English) "As of Sept. 22 this year, voluntary evacuees totaled 50,327, including 26,776 who lived outside the prefecture"

http://www.bloomberg.com/news/2011-12-08/tepco-shares-fall-after-mainichi-report-on-government-takeover.html [Broken] (English) "Tepco faces claims from as many as 1.5 million people for damages, a government panel said yesterday"

http://www.minpo.jp/view.php?pageId=4144&blockId=9910270&newsMode=article Minowa ski resort, Inawashiro town, Fukushima prefecture has opened. The radiation was 0.12 μSv/hour before snow fall. According to related people, the snow offers shielding from ground radiations.

Niigata:
http://mytown.asahi.com/niigata/news.php?k_id=16000001112050002 [Broken] 0.03~0.05 μSv/hour on the slopes at Akakura ski resort. 0.1 μSv/hour or less at Yuzawa ski resort.

http://mainichi.jp/area/niigata/news/20111206ddlk15040226000c.html [Broken] 0.036~0.071 μSv/hour at Suginosawa ski resort.

Shizuoka:
http://mainichi.jp/area/shizuoka/news/20111125ddlk22040250000c.html [Broken] No iodine or cesium detected in school lunches on 17 November, the lunch cooking center for Yoshino town and Makinohara city announced on 24 November.

Gunma:
http://sankei.jp.msn.com/region/news/111207/gnm11120702300002-n1.htm There is a tradition of opening holes in ice for fishing smelt in Akagi Onuma Lake, from January to March. However, as fish has been found above 500 Bq/kg, fishing is banned.

http://www.jfa.maff.go.jp/e/inspection/pdf/111129_gunma_en.pdf (English) "The result of the inspection obtained on 29 November showed that radioactive cesium exceeded the provisional regulation value. In response to this, the Gunma Prefectural Government decided to maintain the request to postpone the opening day for fishing season for Japanese smelt and to voluntarily refrain from catching other edible fish species (Japanese dace, common carp and trout) in Akagi-onuma Lake."

Yamanashi:
http://www.jfa.maff.go.jp/e/inspection/pdf/111129_yamanasi_en.pdf (English) "Although far below the provisional regulation value, radioactive materials were detected in the kokanee and Japanese smelt samples taken from the lakes in Yamanashi prefecture except for the Japanese smelt sample of Shoji Lake."

Hyogo:
http://www.jfa.maff.go.jp/e/inspection/pdf/111021_hyogo_en.pdf (21 October) "Radioactivity was not detected in the Pacific oyster sample inspected this time"

Tokyo:
http://www.jfa.maff.go.jp/e/inspection/pdf/111117_tokyo_en.pdf (17 November) Japanese spiny lobster and Horned turban: Cs/Iodine "Not detectable"

Kanagawa:
http://www.jfa.maff.go.jp/e/inspection/pdf/111111_yokohama_en.pdf 14 fisheries products fished from 5 September to 9 November: from "not detectable" to 19 Bq/kg (tidepool gunnel).
http://www.jfa.maff.go.jp/e/inspection/pdf/111208_kanagawa_en.pdf 4 fish species, between "not detected" and 9 Bq/kg (bullet tuna)
http://www.jfa.maff.go.jp/e/inspection/pdf/111205_kanagawa_en.pdf dried laver seaweed : not detected.
http://www.jfa.maff.go.jp/e/inspection/pdf/111124_kanagawa_en.pdf 9 fish species, between "not detected" and 14 Bq/kg (seabass)

Chiba:
http://www.jfa.maff.go.jp/e/inspection/pdf/111208_tiba_en.pdf 17.7 Bq/kg in dried laver seaweed; 2.7 Bq/kg in anchovy
http://www.jfa.maff.go.jp/e/inspection/pdf/111205_tiba_en.pdf 1.57 Bq/kg in anchovy : 12.1 Bq/kg in amberjack
http://www.jfa.maff.go.jp/e/inspection/pdf/111202_tiba_en.pdf 7.3 Bq/kg in alfonsino fish; nothing detected in habanori seaweed
http://www.jfa.maff.go.jp/e/inspection/pdf/111201_tiba_en.pdf 1.46 Bq/kg in anchovy.
http://mdn.mainichi.jp/mdnnews/news/20111202p2a00m0na007000c.html [Broken] (English) "The average amount of xenon-133 in the atmosphere was 1,300 becquerels per cubic meter of air in Chiba between March 14 and 22"

Miyagi:
http://www.jfa.maff.go.jp/e/inspection/pdf/111207_miyagi_en.pdf 20 species of fish: from "not detected" to 61 Bq/kg (Japanese sandlance)
http://www.jfa.maff.go.jp/e/inspection/pdf/111130_miyagi_en.pdf 9 species of fish: from "not detected" to 24 Bq/kg (olive flounder)

Saitama:
http://edition.cnn.com/2011/12/07/world/asia/japan-baby-formula/ 22 to 31 Bq/kg baby milk: "Ingredients of the baby powder may have come into contact with airborne radioactive cesium when they were being dried at a factory in Kasukabe, (...) between March 14 and 20"
 
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  • #464
http://www.yomiuri.co.jp/dy/editorial/T111215005195.htm [Broken] "Local education and school officials have been perplexed by the Education, Culture, Sports, Science and Technology Ministry's announcement of its own criteria limiting radioactive substances in the food and drink served in school meals to 40 becquerels per kilogram. (...) The Health, Labor and Welfare Ministry (...) is scheduled to announce new limits for different food items by the end of this year".

Fukushima:
http://radioactivity.mext.go.jp/ja/1910/2011/12/1910_1216.pdf [Broken] This is the result of the 4th helicopter monitoring campaign in the 80 km range around the plant (16 December press release). The 3rd campaign had been started on 30 May and its results were publicly released on 8 July. The 4th campaign was performed from 22 November to 5 December. On page 21/34 there is a differential map (4th campain minus 3rd campaign). On page 22/34 we have the distribution diagram of the (4th campain / 3rd campain) ratio. On page 23/34 we have the map of (4th campain / 3rd campain) ratios. On page 12/34 we have a differential map of (3rd campain minus 1st campain): many differences are a result of using different measuring methods, such as the helicopter traveling on different trajectories. On pages 13/34 and 14/34, if my understanding is correct, they explain that some of the shapes that had been shown in the 3rd-1st differential map disappeared in the 4th-1st differential because in the 4th campaign the same trajectories as in the 1st campaign were also used. The maps on pages 26 and 27 are 4th/3rd ratio maps for the study of rivers. The page 28/34 map provides July, August, September, October rainfalls. The page 29/34 map provides rainfalls for specific high rainfall events : July 17-21 typhoon No. 6, July 27-31 stationary front, September 1-4 typhoon No. 12, September 19-22 typhoon No. 15. As a whole the difference between the 3rd and the 4th campain is 11%. 9.2% is thought to be due to the decay rate decrease, and an additional 1.8% is thought to be due to other causes. It has not been possible to characterise the factors of the local changes [to correlate the changes with a set of factors ?], but it is thought that some of them are due to changes in lake or sea levels, flying direction, missing values. It is thought that in some river mouths or river shallows, radiation increase is due to radioactive substance migration.

http://www.mhlw.go.jp/english/topics/2011eq/level_dec15.html 39 Bq/kg in beef in Shirakawa city, 14 December.

http://ajw.asahi.com/article/0311disaster/fukushima/AJ201112170002 [Broken] Iitate village: "the plan is to reduce the annual dose of external radiation exposure to 5 millisieverts (...) begin moving residents back in two years' time and have them all returned within five years".

http://ajw.asahi.com/article/0311disaster/fukushima/AJ201112060035 [Broken] "No cesium" goal in agricultural products: "According to the prefectural government's plan, soil up to about 30 centimeters deep will be replaced in rice paddies and fields to prevent crops from absorbing cesium from roots. In orchards, tree bark and branches will be cut off"

Miyagi:
http://mainichi.jp/area/miyagi/news/20111217ddlk04040073000c.html [Broken] A study of Miyagi prefecture rivers and lake has been released by the ministry of environment. Cesium was found in water only in one out of 138 tested locations, with 3Bq/kg. 11,000 Bq/kg was found in the mud at the bottom of Nanakita river in Sendai. As a whole, 21 locations were found with river mud above 1000 Bq/kg. The radiation is comparatively higher close to river mouths.

http://www.env.go.jp/jishin/monitoring/result_pw111216-1.pdf Miyagi prefecture river monitoring results

Tochigi:
http://sankei.jp.msn.com/region/news/111217/tcg11121702120004-n1.htm The ministry of environment released a Tochigi prefecture river and lake survey. In one location 1 Bq/l was found in water. 4900 Bq/kg was found in river bottom mud in Nikko. They also checked the Earth in areas surrounding rivers, and found 9400 Bq/kg of Cs137 in Nasu.

http://www.env.go.jp/jishin/monitoring/result_pw111216-2.pdf Tochigi prefecture river monitoring results

http://www.mhlw.go.jp/english/topics/2011eq/level_dec15.html 551 Bq/kg in deers in Nikko (15 December).

Ibaraki:
http://www.env.go.jp/jishin/monitoring/result_pw111202.pdf Ibaraki prefecture river monitoring results

Chiba:
http://mainichi.jp/area/chiba/news/20111217ddlk12040102000c.html [Broken] It was announced that Kashiwa city's south waste incinerating facility would suspend operations on 5 January, because they have nowhere to store the ashes above 8000 Bq/kg which cannot be recycled. So Far they have produced 176 tons of such ash and stored them in 848 drums. They have free space for 150 drums, which is just about enough for the end of the year. As a whole, Kashiwa city has 450 tons of 8000Bq/kg or above ash. All the city's waste will then be processed at the North waste incinerating facility, which produces low contaminated ashes because the ashes are no longer concentrated like in the former processing method. In June, 78,000 Bq/kg had been found in the ashes at the South facility.

Kanagawa:
http://ajw.asahi.com/article/0311disaster/fukushima/AJ201112160019 [Broken] Yokohama strontium: "The Isotope Research Institute, (...) maintained that another analytical method had confirmed the presence of strontium (...) excluded the possibility of contamination from lead".

Kochi:
http://www.j-cast.com/2011/12/16116623.html 2.17 Bq/kg in returning bonitos. [Bonitos swim to the north in summer and swim back to south in autumn]

Hokkaido:
http://www.mhlw.go.jp/english/topics/2011eq/level_dec15.html 15 Bq/kg in pacific cod (7 December).
 
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  • #465
joewein said:
I am curious when the radiation maps from the helicopter surveys for Hokkaido will be published.

Probably not before the snow melts.

tsutsuji said:
http://www3.nhk.or.jp/news/genpatsu-fukushima/20110823/0445_jokusenryo.html Helicopter borne radiation surveys will be started before next October in 22 prefectures from Aomori to Aichi. The surveys must be done before snow starts falling.
 
  • #466
http://www.yomiuri.co.jp/national/news/20111222-OYT1T01049.htm [Broken] On 22 December, the ministry of Health announced the new food safety levels that will be applied to food against cesium from April 1: cereals, vegetables, fish, meat: 100 Bq/kg instead of the present 500 Bq/kg. Drinking water: 10 Bq/kg instead of 200 Bq/kg. Milk and baby food: 50 Bq/kg instead of 200 Bq/kg. The new levels are set in function of a maximum internal contamination by food of 1 mSv/year. The most severe group for general food was the 13-18 years old males which required the 100 Bq/kg limit.

http://www3.nhk.or.jp/news/genpatsu-fukushima/20111225/1815_guide.html The ministry of Environment released a contaminated waste storage guideline. A government panel said it is OK to reuse 3000 Bq/kg or less concrete if buried under more than 30 cm, and such concrete could be used this way in roads or seawalls.

http://www3.nhk.or.jp/news/genpatsu-fukushima/20111226/1930_hinan_kuiki.html The evacuation zones will be reorganised. The areas below 20 mSv/year will be named " evacuation-order-lifting-prepared areas", those between 20 and 50 mSv/year "living-restricted areas", those above 50 mSv/year "hard-to-go-back-home areas".

http://www3.nhk.or.jp/news/genpatsu-fukushima/20111219/1745_josen.html Japan's national government will pay the costs of decontamination in all areas above 1 mSv/year (0.23 microSv/hour), in 102 cities and villages in 8 prefectures (Iwate: 3, Miyagi: 8, Fukushima: 40, Ibaraki: 20, Tochigi: 8, Gunma: 12, Saitama: 2, Chiba: 9).

Iwate:
http://www3.nhk.or.jp/news/genpatsu-fukushima/20111220/0645_josen.html The producers of the « Maezawa beef » brand are unhappy to learn that their city, Oshu, was designated among the 102 cities and villages with government-paid decontamination. They say that only one part of their city is highly contaminated.

Fukushima:
http://wwwcms.pref.fukushima.jp/download/1/suiden_kinkyu_1222.pdf 1450 Bq/kg in rice in one farm in Fukushima city, former Fukushima city.

http://wwwcms.pref.fukushima.jp/download/1/suiden_kinkyu_1228_1.pdf The histogram on page 2 shows the cesium concentration distribution among the 5291 samples in 4480 rice growing farms in 6 cities (22 former villages) tested between November 28 and December 28. (the largest histogram is for the 4197 samples where cesium was not detected)

http://wwwcms.pref.fukushima.jp/download/1/suiden_kinkyu_1230.pdf one farm found with 550 Bq/kg rice in Date city, former Sekimoto village.

http://www.yomiuri.co.jp/national/news/20111225-OYT1T00595.htm [Broken] Analysis investigating the reason why some of the rice harvested in Fukushima prefecture had high cesium concentrations showed that the soil in the concerned rice fields contains lower concentrations of potassium and that the roots were shallow, while the top soil layer is more contaminated than the lower layer.

http://www.yomiuri.co.jp/national/news/20111224-OYT1T00981.htm [Broken] 18% of parents say they will send their children to the school which is planning reopening in Kawauchi next April.

Gunma:
http://www.tokyo-np.co.jp/article/gunma/20111224/CK2011122402000074.html [Broken] Detailed analysis of the high cesium smelt in Akagi Onuma lake (elevation 1300 m) will be performed, such as opening the stomach and testing what they eat, or testing the mud at the bottom of the lake.
 
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  • #467
  • #468
tsutsuji said:
http://www3.nhk.or.jp/news/genpatsu-fukushima/20111226/1930_hinan_kuiki.html The evacuation zones will be reorganised. The areas below 20 mSv/year will be named " evacuation-order-lifting-prepared areas", those between 20 and 50 mSv/year "living-restricted areas", those above 50 mSv/year "hard-to-go-back-home areas".

http://www3.nhk.or.jp/news/genpatsu-fukushima/20111219/1745_josen.html Japan's national government will pay the costs of decontamination in all areas above 1 mSv/year (0.23 microSv/hour), in 102 cities and villages in 8 prefectures (Iwate: 3, Miyagi: 8, Fukushima: 40, Ibaraki: 20, Tochigi: 8, Gunma: 12, Saitama: 2, Chiba: 9).

And here we have an object lesson in the real costs of nuclear power. Hard to go back home, indeed.

Why isn't TEPCO paying for the decon? Seriously.
 
  • #469
Gary7 said:
Ministry of Education is reporting cesium fallout in Fukushima city in the past several days. Figures for January 2nd - 3rd are 180MBq/km2 of Cesium 134, and 252MBq/km2 of Cesium 137.

No explanation for the rise. Internet chatter starting to heat up with speculation.

http://money.jp.msn.com/news/yucasee/article.aspx?cp-documentid=5727817

The Safecast discussion list has a very informative thread on the subject:

http://groups.google.com/group/safe...ca5cead348e/73f9fd6bec0ad8d6#73f9fd6bec0ad8d6

In a nutshell: The readings peaked at 400Mbq/km2 or 400 Bq/m2; parts of Fukushima are measuring 50kBq/m2 to 2MBq/m2 so this is a minuscule amount. Thermal cycling and ground freezing probably disturbed the upper layer of soil, giving higher readings, and the high winds those days probably picked up some contaminated soil and redistributed it. No iodine was detected anywhere either, so that indicates no new releases. Finally, Prof Hayano posted a graph linking windspeed to Cs levels:

http://twitpic.com/843z4d

I was dismayed at how quickly the internet rumor mill in Japan snowballed this into a crisis of some sort. One poster on FB said,
"My wife has a freaky friend who called us to say she is packing to go to Oita because she learned on the net that no. 4 is approaching critical."
That's like someone in NYC saying they're evacuating to Florida. On Safecast a poster said,
"On January 5 and 6 the Japanese portion of Twitter is was buzzing with traffic on this subject. A Gunderson video video telling people to flee in case Dai-ichi Reactor 4 collapses was circulated via the internet, and some people were saying that they were so worried that they did not feel like going to work. The information that Iwaki residents recently received new iodine tablets because the shelf dates of earlier distributed tablets had expired, was also taken out of context to mean that some new nuclear event was possibly unfolding. "

Neither MEXT nor TEPCO anticipated the reaction and so neither provided timely explanation. I fault them for this. And the reaction shows how on edge people still are. True, there are lots of voices spreading bad information and amplifying the anxiety, but the fear is real nevertheless.
 
  • #471
Thermal cycling and high winds have been a constant worry for me:smile:
 
  • #472
Gary7 said:
Ministry of Education is reporting cesium fallout in Fukushima city in the past several days. Figures for January 2nd - 3rd are 180MBq/km2 of Cesium 134, and 252MBq/km2 of Cesium 137.

No explanation for the rise. Internet chatter starting to heat up with speculation.

http://money.jp.msn.com/news/yucasee/article.aspx?cp-documentid=5727817
Azby said:
In a nutshell: The readings peaked at 400Mbq/km2 or 400 Bq/m2; parts of Fukushima are measuring 50kBq/m2 to 2MBq/m2 so this is a minuscule amount.

Let's see how minuscule. The groundshine coefficients for Cs 134 and Cs 137 are provided at http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/dose/largetable-longtableau-eng.php [Broken]

For Cs 134 we have 180 Bq/m² * 1.48 E-15 * 3600 = 0.96 nanosievert/hour = 0.00096 microsievert/hour of groundshine

For Cs 137 we have 252 Bq/m² * 5.51 E-16 * 3600 = 0.50 nanosievert/hour = 0.00050 microsievert/hour of groundshine

Do you have a clue on how the inhalation dose can be estimated ? In order to apply the inhalation coefficients, knowing that an adult breathes 22.2 m³/day ( http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/dose/summary-resume-eng.php#table2 [Broken] ), one needs radiation measurements in Bq/m³. Is there a way to estimate them from the Bq/m² values, or do we need a specific measurement ?
 
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  • #473
tsutsuji said:
Let's see how minuscule. The groundshine coefficients for Cs 134 and Cs 137 are provided at http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/dose/largetable-longtableau-eng.php [Broken]

For Cs 134 we have 180 Bq/m² * 1.48 E-15 * 3600 = 0.96 nanosievert/hour = 0.00096 microsievert/hour of groundshine

For Cs 137 we have 252 Bq/m² * 5.51 E-16 * 3600 = 0.50 nanosievert/hour = 0.00050 microsievert/hour of groundshine

Do you have a clue on how the inhalation dose can be estimated ? In order to apply the inhalation coefficients, knowing that an adult breathes 22.2 m³/day ( http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/dose/summary-resume-eng.php#table2 [Broken] ), one needs radiation measurements in Bq/m³. Is there a way to estimate them from the Bq/m² values, or do we need a specific measurement ?

We can use the data of dust monitoring from Fukushima City, but I do not know where the sampling point (Sugitsuma town) is located in relation with the fallout sampling point:

Readings of dust sampling (June 1, 2011 - January 19, 2012)

Radioactivity Concentration (Bq/m^3) Cs-134 Cs-137
2011/12/27 - 2011/12/28 ND 0.000310
2011/12/28 - 2011/12/29 0.000379 0.000331
2011/12/29 - 2011/12/30 0.00138 0.00171
2011/12/30 - 2011/12/31 0.000468 ND
2011/12/31 - 2012/1/1 0.000424 0.000482
2012/1/1 - 2012/1/2 0.000727 0.00103
2012/1/2 - 2012/1/3 0.00130 0.00164
2012/1/3 - 2012/1/4 0.000994 0.00120
2012/1/4 - 2012/1/5 0.000642 0.000813
2012/1/5 - 2012/1/6 ND ND
2012/1/6 - 2012/1/7 0.000417 0.000335
2012/1/7 - 2012/1/8 0.000506 0.000922
2012/1/8 - 2012/1/9 0.000635 0.000748
2012/1/9 - 2012/1/10 0.00126 0.00136
2012/1/10 - 2012/1/11 0.000891 0.000716
2012/1/11 - 2012/1/12 ND 0.000380
2012/1/12 - 2012/1/13 0.000680 0.000930
2012/1/13 - 2012/1/14 0.000504 0.000601
2012/1/14 - 2012/1/15 0.000702 0.000974
2012/1/15 - 2012/1/16 0.00183 0.00235
2012/1/16 - 2012/1/17 0.00108 0.00134​

Detection limits are 0.0003Bq/m^3 for Cs-134 and 0.0003Bq/m^3 for Cs-137
 
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  • #474
Sorai said:
Radioactivity Concentration (Bq/m^3) Cs-134 Cs-137
2012/1/15 - 2012/1/16 0.00183 0.00235
Thank you.

According to http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/dose/largetable-longtableau-eng.php [Broken] , the inhalation dose coefficient are 6.6 nSv/Bq for Cs 134 and 4.6 nSv/Bq for Cs 137
According to http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/dose/summary-resume-eng.php#table2 [Broken] , an adult breathes 22.2 m³/day

0.00183 * 6.6 * 22.2/24 = 0.011 nSv/hour by inhalation of Cs 134
0.00235 * 4.6 * 22.2/24 = 0.010 nSv/hour by inhalation of Cs 137

According to http://www.hc-sc.gc.ca/ewh-semt/pubs/radiation/dose/largetable-longtableau-eng.php [Broken] , the cloudshine dose coefficients are 7.06e-14 Sv/(s*Bq/m³) for Cs 134 and 2.55e-14 Sv/(s*Bq/m³) for Cs 137

0.00183 * 7.06e-14 * 3600 = 4.65 e-13 Sv/hour = 0.000465 nSv/hour by Cs 134 cloudshine
0.00235 * 2.55e-14 *3600 = 2.15 e-13 Sv/hour = 0.000215 nSv/hour by Cs 137 cloudshine

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120111/1720_camera.html Toshiba is testing a gamma ray camera in Fukushima city, looking how it could be helpful for decontamination work. The problem is that currently it takes 10 minutes to take a picture.

http://mdn.mainichi.jp/mdnnews/news/20120113p2g00m0dm013000c.html [Broken] "The average radiation exposure of some 37,000 residents in Fukushima city following the nuclear crisis at the Fukushima Daiichi power plant came to 0.26 millisieverts during the three-month period from September, the municipal government said Thursday [12 January]."

http://mdn.mainichi.jp/mdnnews/news/20120111p2a00m0na021000c.html [Broken] "Chiba Prefecture troubled by shrinking population after nuclear disaster"

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120113/0545_doukou.html Fukushima residents are now allowed to have a company to come along when they pay a temporary visit at their house in the restricted zone. This will help them to perform repairs or to carry their belongings. [What if the said belongings are contaminated? And what about company workers' health?]

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120115/0420_kensa.html The national government and Fukushima prefecture are going to test breast milk with around 10,000 mothers.

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120123/index.html The government is studying how food producers can be compensated for losses due to the changing of the food safety levels (100 Bq/kg instead of 500 Bq/kg for general food from 1 April), as the consumers might refrain from consuming some products even before 1 April.
 
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  • #475
Any updates on the levels of seawater contamination? The regular info seems to have dried up.
 
  • #476
Caniche said:
Any updates on the levels of seawater contamination? The regular info seems to have dried up.


You mean this one:

http://www.tepco.co.jp/en/nu/fukushima-np/f1/index9-e.html
 
  • #477
http://www.manchester.ac.uk/research/news/display/?id=7895 [Broken]

this thing could solve a lot of problems...
 
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  • #478
Nice stuff.
 
  • #479
http://www3.nhk.or.jp/news/genpatsu-fukushima/20120124/index.html As a countermeasure decided after finding that contaminated stones were delivered from a contaminated stone pit in Namie, the government is goint to check construction materials from the restricted zone. The namie stones were used in the concrete which was used to build a new appartment building in Nihonmatsu and high radiation levels were measured inside the appartments. A report will be issued within this month. Concerning the preparation of national safety level for construction materials, the nuclear disaster response headquarters said "it will take time to study it".

http://mainichi.jp/select/jiken/news/20120127ddm041040045000c.html [Broken] A decontamination roadmap was released on 26 January. According to the mayor of Namie, almost nothing is scheduled for the above 50 mSv zone.

http://josen.env.go.jp/index.html new decontamination website

http://www.env.go.jp/press/press.php?serial=14747 decontamination roadmap

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120128/index.html helicopter surveys are starting in Nagasaki, Saga, and Fukuoka prefectures on 30 January. Hokkaido's helicopter survey will start after snow melts.

http://radioactivity.mext.go.jp/ja/1910/2012/01/1910_012714.pdf [Broken] Helicopter survey schedule for Western Japan and Hokkaido

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120127/2030_gyokyou.html experimental fishing in close waters off Fukushima prefecture was planned in February, but it is being postponed because some of the fish tested are higher than the provisional safety level.
 
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  • #480
http://www.mhlw.go.jp/stf/houdou/2r98520000021b3t.html (27 January 2012) Opinion request about the revision of food screening methods to be applied from 1 April. Opinions must be written in Japanese and received by 13 February.

http://www.mhlw.go.jp/stf/houdou/2r98520000021anu-att/2r98520000021aru.pdf (27 January press release) Drinking water results in a number of Tohoku and Kanto cities. All the data are "ND" (not detected")

http://www.mhlw.go.jp/stf/houdou/2r98520000021cq3-att/2r98520000021ctw.pdf (radioactive substances in food, report No. 306 of 27 January 2012, Rice farming department, press release of 24 January 2012) : two farms in Date city, former Oguni village, Fukushima prefecture were found above level. Farm A : 700 Bq/kg, and farm B : 1,110 Bq/kg.
 
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  • #482
Yamanote said:
The second part of this animation shows, what would have happened in case of an accident on the other side of Japan:

http://www.youtube.com/watch?v=CEFt9p7-Dxo

A bit disingenuous... are there such tsunamis on the other coast? I thought not.
But then, it's not the only possible accident cause.
 
  • #483
zapperzero said:
A bit disingenuous... are there such tsunamis on the other coast? I thought not.
But then, it's not the only possible accident cause.

The 1983 Sea of Japan tsunami swept along a wide part of the Sea of Japan coast, from the Noto peninusla north, reached ten metres in height and and killed about one hundred people including some on the Korean peninsula. Kashiwazaki has tsunami protection for a reason!

The animation shows a plant in Fukui spewing radiation on Nagoya; if you shift the scenario north Noto peninusla to Kashiwazaki then the same plume would be right over Tokyo. It is a pretty crudely drawn scenario, but the risk is there.

Cheers,
James
 
  • #484
Another example: The 1993 Hokkaido earthquake.

The tsunami inundated large parts of Okushiri, despite its tsunami defenses. A maximum run-up of 32 m was recorded on the western part of the island near Monai. A tsunami was widely observed in the Sea of Japan with a run-up of 3.5 m at Akita in northern Honshu, up to 4.0 m in southeastern Russia and up to 2.6 m on the coast of South Korea.[4]

Location of Okushiri: Northern part of the Sea of Japan.

Hokkaido_Okushiri-town.png


Furthermore, the height of Tsunamis is not only determinated by the force of the earthquake, but also by the shape of the coast. It's possible that Kashiwazaki-Kariwa stands at a location which is insensitive to Tsunamis.

Example Kamaishi:

http://www.nytimes.com/interactive/2011/11/02/world/asia/A-Tsunami-Defense-Under-Scrutiny.html

There are two bays, directly besides each other. But the Tsunami height flcutuates between 30 and 100 feet.
Notice the difference between the points "E" and "F".
 
  • #485
http://sankei.jp.msn.com/region/news/120127/fks12012722390005-n1.htm 39 bags (57.5 kg) of rice from the 1100 Bq/kg farm have been sold. The prefecture ordered the recall of the bags. This is the second occurrence of contaminated rice being sold. Until now 38 rice farms in 3 cities and one town have been found above safety level.

http://www.sankeibiz.jp/compliance/news/120126/cpd1201261430014-n1.htm [Broken] In 2012, rice planting in the areas that harvested rice contaminated between 100 and 500 Bq/kg in 2011 will be subject to conditions such as low risk (when the number of samples found above 100 Bq/kg was small) and decontamination measures, the Fukushima Central Union of Agricultural Cooperatives announced. Concerning the areas where rice was not grown in 2011, the conditions will be set after the full test results of the 2011 harvests are known. The Fukushima Central Union of Agricultural Cooperatives also said that in 2012, 100% of the bags will be tested, and whenever a radiation, even a small one, is detected, they will not be shipped. The ministry of agriculture indicated at the end of last year its intention to restrict rice planting in the areas where crops higher than 500 Bq/kg were harvested. Concerning the areas where crops were found between 100 and 500 Bq/kg, the policy will be decided after consulting with the prefecture and growers.

http://www.47news.jp/CN/201201/CN2012012701002644.html [Broken] The ministry of health announced that the detection threshold for general food testing that is to be applied from 1 April, is set at 25 Bq/kg instead of the present 50 Bq/kg. Public comments on this measure are open till 13 February.

http://www.chunichi.co.jp/article/nagano/20120117/CK2012011702000125.html [Broken] Nagano prefecture has started testing each mushroom growing farm. The 600 farms will be tested until March.

http://www.hiroshimapeacemedia.jp/mediacenter/article.php?story=20120126102721779_ja (Chugoku Shimbun, 26 January morning edition) Professor Toshihiro Takatsuji of Nagasaki university announced at an international symposium at Hiroshima university on 25 January that high radiation levels were found in Nagasaki one month after the accident. The Cs 134 concentration on paper filters was 11,300 Bq/kg during the week from 6 April 2011. Using US National Oceanic and Atmospheric Administration data, he found that on 6 April, the southern half of Japan was blown by winds from Tohoku. He said that even if the atmopheric radiation value is low, it is possible that it increases in locations where radioactive substances accumulate, such as on air conditioner filters.

http://www.minpo.jp/view.php?pageId=4107&blockId=9927368&newsMode=article (Fukushima Minpo, 26 January) the Study committee announced the results of the thyroid examination of the children 18 years old or below from Namie, Iitate and Kawamata. Among 3765 people tested, zero were found necessitating immediate second examination, 26 were found necessitating a second examination, and 1117 with stiffnesses of 5 mm or below, which are considered benign. According to the vice-president of Fukushima medical university, there is no malignity variation due to the nuclear accident.
 
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  • #486
Fukushima:
http://ajw.asahi.com/article/0311disaster/fukushima/AJ201201270048 [Broken] The government's decontamination roadmap is setting up a 1 microsievert/hour goal in schools, and a 10 mSv/year goal elsewhere in the 10-20 mSv/year zone.

http://www.yomiuri.co.jp/e-japan/fukushima/news/20120203-OYT8T00012.htm [Broken] 140 samples have been above 500 Bq/kg among 2125 Fukushima Prefecture shallow (less than 50 m deep) water sea fish samples tested since April.

http://mdn.mainichi.jp/mdnnews/news/20120206p2a00m0na008000c.html [Broken] worms around the plant ingest large quantities of cesium. It is feared that other animals that eat worms might in turn be contaminated.

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120207/index.html Tepco will compensate cars, busses, and trucks broken because they were left without maintenance, or because they were not allowed to leave the restricted area because their radiation doses were too high.

http://mdn.mainichi.jp/mdnnews/national/news/20120209p2a00m0na013000c.html [Broken] [temporary] "Radioactive waste disposal site unveiled to reporters" [in Hirono, Fukushima prefecture].

Elsewhere in Japan:
http://www.okinawatimes.co.jp/article/2012-01-31_29251/ [Broken] 1.12 Bq/kg of cesium was found in eringi mushrooms grown in Nagano and eaten by schoolchildren in a south Okinawa Island school in November.

http://mytown.asahi.com/yamagata/news.php?k_id=06000001201310003 [Broken] Two roadside ditches above 8000 Bq/kg have been found in a survey of 26 locations in 12 cities and towns in Yamagata prefecture. 19400 Bq/kg was found in Tendo, and 17400 Bq/kg in Sagae. The radiation at 1 m above ground was 0.13 microsievert/hour in both cases.

http://www.tokyo-np.co.jp/article/gunma/20120131/CK2012013102000059.html [Broken] 473 and 480 Bq/kg in wakasagi fish, and 768 Bq/kg in iwana trouts in Akagi Oonuma lake, Gunma prefecture. Fishing remains restricted.

http://sankei.jp.msn.com/region/news/120209/kng12020921550005-n1.htm 2077 Bq/kg dried shiitake mushrooms grown in Shizuoka were found in a shop in Yokohama. 7 bags (of 80 g each) have already been sold.
 
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  • #487
tsutsuji said:
Elsewhere in Japan:
http://www.okinawatimes.co.jp/article/2012-01-31_29251/ [Broken] 1.12 Bq/kg of cesium was found in eringi mushrooms grown in Nagano and eaten by schoolchildren in a south Okinawa Island school in November.

Is this right? Natural radiation (mostly from K-40) in human body is around 50 Bq/kg. Additional 1.12 Bq/kg in food is practically negligible - especially considering that it's Cs, which does not bioaccumulate in humans.
 
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  • #488
It is right, I think. The article says it is 0.46 Bq/kg of Cs-134 and 0.66 Bq/kg of Cs-137. I think that it is a problem that this article (like most articles about food) does not mention the presence of K-40 in bananas or other foods. People reading the article may unnecessarily worry too much.
 
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  • #489
tsutsuji said:
http://sankei.jp.msn.com/region/news/120209/kng12020921550005-n1.htm 2077 Bq/kg dried shiitake mushrooms [STRIKE]grown in Shizuoka[/STRIKE] were found in a shop in Yokohama. 7 bags (of 80 g each) have already been sold.

Grown mainly in Iwate and packaged in Shizuoka. Sorry.

http://www.nikkei.com/news/category...E2E2E1828DE3E2E2E0E0E2E3E09180EAE2E2E2;av=ALL As a follow-up of the discovery in January of 43,780 Bq/kg high radiation ashes in a wood stove in Nihonmatsu, Fukushima prefecture, the ministry of environment checked wood stoves in 9 homes in 9 cities and towns in Southern Ibaraki prefecture . The lowest value was 1180 Bq/kg and the highest one 59,000 Bq/kg (resulting of the burning of 480 Bq/kg wood).

http://mainichi.jp/life/food/news/20120211ddm012040016000c.html [Broken] 258 Bq/kg in soba noodles in a restaurant in Okinawa. The noodles were manufactured using water percolating ashes from Fukushima wood. On 10 February, the Forestry Agency issued instructions so that wood from 17 prefectures produced after the 11 March earthquake are not used in food, even if they are below the radiation limits (40 Bq/kg for wood, 280 Bq/kg for charcoal).

http://mainichi.jp/select/weathernews/news/20120210ddm001040046000c.html [Broken] List of cities and towns in Fukushima prefecture where the 2011 rice harvest was found higher than 100 Bq/kg, with the numbers of such farms (170 farms in Fukushima city, 199 in Date, 111 in Nihonmatsu, 39 in Kunimi, 29 in Koori, 20 in Motomiya, 6 in Kawamata, 2 in Ootama and Soma, 1 in Tamura and Shirakawa) (Higher than 500 Bq/kg: 23 Farms in Fukushima city, 14 in Date, 1 in Nihonmatsu).
 
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  • #490
A year [actually 11 months, but it seems it will go on] on, only brief home visits for Japan nuclear evacuees
http://news.yahoo.com/only-brief-home-visits-japan-nuclear-evacuees-081517728.html [Broken]
 
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<h2>1. What are the potential health consequences of the Japan earthquake and radiation contamination outside of the Fukushima NPP?</h2><p>The potential health consequences of the Japan earthquake and radiation contamination outside of the Fukushima NPP include increased risk of cancer, particularly thyroid cancer, due to exposure to radioactive particles. Other potential health effects may include radiation sickness, birth defects, and genetic mutations.</p><h2>2. How far has the radiation from the Fukushima NPP spread?</h2><p>The radiation from the Fukushima NPP has spread primarily to the surrounding areas in Japan, with some contamination reaching as far as North America and Europe. However, the levels of radiation in these areas are considered low and not a significant health concern.</p><h2>3. What measures have been taken to contain the radiation from the Fukushima NPP?</h2><p>The Japanese government has implemented a 20-kilometer exclusion zone around the Fukushima NPP and has also conducted decontamination efforts in the surrounding areas. Additionally, the plant operators have built a steel and concrete barrier to prevent further leakage of radioactive materials into the environment.</p><h2>4. Is it safe to consume food and water from Japan after the earthquake and radiation contamination?</h2><p>The Japanese government has strict regulations in place to monitor food and water for radiation levels. As long as these regulations are followed, it is generally considered safe to consume food and water from Japan. However, some countries have imposed restrictions on certain food imports from Japan as a precautionary measure.</p><h2>5. How long will the effects of the radiation from the Fukushima NPP be felt?</h2><p>The long-term effects of the radiation from the Fukushima NPP are still being studied and are difficult to predict. However, it is estimated that the area around the NPP may be uninhabitable for several decades. The health effects on individuals who were exposed to radiation may also be felt for many years to come.</p>

1. What are the potential health consequences of the Japan earthquake and radiation contamination outside of the Fukushima NPP?

The potential health consequences of the Japan earthquake and radiation contamination outside of the Fukushima NPP include increased risk of cancer, particularly thyroid cancer, due to exposure to radioactive particles. Other potential health effects may include radiation sickness, birth defects, and genetic mutations.

2. How far has the radiation from the Fukushima NPP spread?

The radiation from the Fukushima NPP has spread primarily to the surrounding areas in Japan, with some contamination reaching as far as North America and Europe. However, the levels of radiation in these areas are considered low and not a significant health concern.

3. What measures have been taken to contain the radiation from the Fukushima NPP?

The Japanese government has implemented a 20-kilometer exclusion zone around the Fukushima NPP and has also conducted decontamination efforts in the surrounding areas. Additionally, the plant operators have built a steel and concrete barrier to prevent further leakage of radioactive materials into the environment.

4. Is it safe to consume food and water from Japan after the earthquake and radiation contamination?

The Japanese government has strict regulations in place to monitor food and water for radiation levels. As long as these regulations are followed, it is generally considered safe to consume food and water from Japan. However, some countries have imposed restrictions on certain food imports from Japan as a precautionary measure.

5. How long will the effects of the radiation from the Fukushima NPP be felt?

The long-term effects of the radiation from the Fukushima NPP are still being studied and are difficult to predict. However, it is estimated that the area around the NPP may be uninhabitable for several decades. The health effects on individuals who were exposed to radiation may also be felt for many years to come.

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