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3 octobre 2014 5 03 /10 /octobre /2014 17:40

Nuclear Watch :

http://www3.nhk.or.jp/nhkworld/english/news/nuclearwatch/20141001.html

Impact of Low-Level Radiation

Scientists from Japan and abroad have been trudging through the abandoned fields and forests of Fukushima looking for clues. They're trying to find out how the radiation released by the damaged nuclear plant there is affecting animals and insects. And some are paying particular attention to how or even if low-level contamination is affecting organisms. NHK WORLD's Craig Dale has the story.

Bug hunting in Fukushima is how biologist Timothy Mousseau spends much of his time in Japan.

The US-based scientist has set up his mobile lab about 30 kilometers northwest of the Fukushima Daiichi nuclear plant.

He's working to find out how insects, birds, and other organisms are affected by different levels of radiation.

 

"Some organisms seem to show consequences and others show no signs whatsoever."
Timothy Mousseau / Professor, University of South Carolina

Mousseau and his colleagues started looking for those signs in July 2011, a few months after the nuclear accident. They've come back to Fukushima prefecture again and again to survey 400 locations.

 

They record radiation levels and note changes in diversity and abundance among other things. Mousseau is particularly interested in the effects caused by low-dose radiation.

 

("They may be small. They may not be of profound significance. But they are measurable and real.) And this is what we really want to know. At what resolution is required to consider an area safe or not?"
Timothy Mousseau / Professor, University of South Carolina

Mousseau's work in Japan has built on his 14 years of research in Ukraine. He's been studying the uninhabited area around the crippled Chernobyl nuclear plant.

 

He's observed even low-level radiation has a negative impact on the abundance of birds and mammals and disrupts development among a variety of organisms.

"This gives us some ability to predict what the consequences could be for human populations even those living in much lower levels of radiation."
Timothy Mousseau / Professor, University of South Carolina

"Scientists studying the impact of the nuclear accident are looking for patterns. They want to see how different levels of radiation are affecting not only individual species, but the entire food chain."
Craig Dale / NHK WORLD

Japanese entomologist Yoshiko Ayabe is also working in Fukushima scouring the forests and collecting samples.

"I think it's necessary to look at areas that are less contaminated."
Yoshiko Ayabe / Nagoya University

In the lab, Ayabe is working to paint a picture of how radiation is making its way up the forest food chain.

Radioactive particles from Fukushima Daiichi fell on trees and made their way into the soil. Plants absorbed them. Then insects ate those plants and other insects ate those insects.

Timothy Mousseau & low-level radiation

Ayabe's results show contamination is relatively low in worms, crickets, and horseflies -- but higher in spiders an apex predator. She says needs to do further research to find out what that means for the entire forest ecosystem.

Timothy Mousseau & low-level radiation

"We have data about Chernobyl, but not about Fukushima. Are the situations the same? We must study to get answers."
Yoshiko Ayabe / Nagoya University

Timothy Mousseau says it will take up to a decade of rigorous work to really understand the impact of the Fukushima nuclear accident. He's calling for a greater investment in research.

 

"So that we can actually answer the questions that people want answers to which is how big an effect does this radiation have? How much radiation is required in order to show an effect of some significance?"
Timothy Mousseau / Professor, University of South Carolina

And so Mousseau will keep coming back to Fukushima in search of answers. To observe how a man-made disaster is playing out in nature and to help figure out what it could mean for people living in this area.

 

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Published by fukushima-is-still-news - dans Health effects of radiation
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30 septembre 2014 2 30 /09 /septembre /2014 20:10

September 29, 2014

Hospitals nominally designated for radiation treatment double from 2011

Kyodo

http://www.japantimes.co.jp/news/2014/09/29/national/science-health/japan-more-than-doubles-the-number-of-hospitals-designated-as-radiation-treatment-centers/#.VCkUkBanp1s

The number of hospitals locally “designated” to treat radiation exposure has grown to 201 from 83 before the Fukushima nuclear disaster, a survey says.

But the survey, conducted by Kyodo News, also showed that the so-called designated hospitals, as of August, were still struggling with shortages of skilled personnel and equipment as central government pushes to restart dozens of idled reactors, many of them old.

The hospitals were designated by local governments as medical institutions that will provide emergency treatment for radiation exposure if nuclear accidents occur. But there are no requirements for receiving the designation — including number of doctors specialized in radiation treatment.

This step was advised through a report compiled by the now-defunct Nuclear Safety Commission after the deadly 1999 criticality accident at a uranium-processing plant in the village of Tokai, Ibaraki Prefecture.

The Nuclear Regulation Authority is reviewing medical preparedness for nuclear disasters as part of a package of initiatives introduced in response to the Fukushima nuclear disaster but has not hammered out any specifics.

The survey was conducted from July to September, 15 years after the criticality accident at JCO Co. in Tokai on Sept. 30, 1999, which killed two people.

Responses were received from all 24 prefectural governments selected for their proximity to nuclear facilities.

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22 septembre 2014 1 22 /09 /septembre /2014 09:14
SPEEDI budget slashed

August 25, 2014

Major budget cut planned for radiation forecasting tool for nuclear accidents

http://ajw.asahi.com/article/0311disaster/fukushima/AJ201408250028

By TOSHIO KAWADA/ Staff Writer

The Nuclear Regulation Authority is planning a major slash in the budget for a forecasting tool for the spread of radioactive substances that was at the center of a controversy during the 2011 Fukushima nuclear accident.

The System for Prediction of Environmental Emergency Dose Information (SPEEDI) was designed to help government officials decide early on whether local residents should be evacuated.

However, a lack of information from the Fukushima No. 1 nuclear power plant made it difficult for the SPEEDI to operate as intended. Moreover, high-ranking government officials at the time, including Prime Minister Naoto Kan and Chief Cabinet Secretary Yukio Edano, were not informed of the existence of the system in the initial stages of the nuclear accident.

With some experts also raising doubts over whether it would be possible to improve the forecasting accuracy of the SPEEDI, the NRA had already downgraded data coming from the system to only "reference material" when it revised in 2013 its guidelines for dealing with nuclear accidents.

For the next fiscal year budget, the NRA will request less than half of what has been budgeted for the SPEEDI this year. About 500 million yen ($4.8 million) has been set aside for maintenance and management of the radioactive contamination forecasting system.

The NRA plans to divert the money that had been going to the SPEEDI for measures that would involve actual measurement of radiation levels.

One such measure is the installation of more monitoring posts in local communities near nuclear plants. Greater emphasis will be placed on actual measurement of radiation levels in deciding if residents should be evacuated in the event of a nuclear accident.

The revised guidelines call for making an evacuation decision for residents living within a 30-kilometer radius of a nuclear plant based on actual measurements from monitoring posts in the area.

In the event of a serious accident that could lead to the emission of large amounts of radioactive materials, residents within a 5-km radius will be ordered to evacuate immediately.

Those living within a radius between 5 kilometers and 30 kilometers will be asked to remain indoors before a decision is made on evacuation based on the actual radiation measurements.

The thinking behind the new guidelines is that quicker and more appropriate decisions can be made based on actual measurements rather than depending on forecasts that may not be totally accurate.

In line with those guidelines, the NRA has begun installing a system for sharing of radiation data among central and local governments. Officials involved in making evacuation decisions will be able to access data on their computer screens as the measurements are being made.

The money that had been going to the SPEEDI will also instead be used to improve the central government's monitoring of the new information-sharing system as well as for its maintenance.

Local governments are being asked to install monitoring posts in areas that could become subject to evacuation. The recommendation has been made to install monitoring posts at intervals of five kilometers depending on whether the area is residential or hilly and also on past spreading of radioactive materials.

Local governments had used the SPEEDI to put together their evacuation plans, and some officials are calling for maintaining the forecasting system.

With the shift toward a new system based on actual measurements, local government officials will now be faced with deciding how to utilize that information and how to transmit it to local residents in the event of a serious nuclear accident.

__________________

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20 septembre 2014 6 20 /09 /septembre /2014 17:16

Childhood Leukemias Near Nuclear Power Stations: new article

http://www.ianfairlie.org/news/childhood-leukemias-near-nuclear-power-stations-new-article/

Posted on July 25, 2014

In March 2014, my article on increased rates of childhood leukemias near nuclear power plants (NPPs) was published in the Journal of Environmental Radioactivity (JENR). A previous post discussed the making of the article and its high readership: this post describes its content in layman’s terms.

Before we start, some background is necessary to grasp the new report’s significance. Many readers may be unaware that increased childhood leukemias near NPPs have been a contentious issue for several decades. For example, it was a huge issue in the UK in the 1980s and early 1990s leading to several TV programmes, Government Commissions, Government committees, a major international Conference, Government reports, at least two mammoth court cases and probably over a hundred scientific articles. It was refuelled in 1990 by the publication of the famous Gardner report (Gardner et al, 1990) which found a very large increase (7 fold) in child leukemias near the infamous Sellafield nuclear facility in Cumbria.

The issue seems to have subsided in the UK, but it is still hotly debated in most other European countries, especially Germany.

The core issue is that, world-wide, over 60 epidemiological studies have examined cancer incidences in children near nuclear power plants (NPPs): most (>70%) indicate leukemia increases. I can think of no other area of toxicology (eg asbestos, lead, smoking) with so many studies, and with such clear associations as those between NPPs and child leukemias. Yet many nuclear Governments and the nuclear industry refute these findings and continue to resist their implications. It’s similar to the situations with cigarette smoking in the 1960s and with man-made global warming nowadays.

In early 2009, the debate was partly rekindled by the renowned KiKK study (Kaatsch et al, 2008) commissioned by the German Government which found a 60% increase in total cancers and 120% increase in leukemias among children under 5 yrs old living within 5 km of all German NPPs. As a result of these surprising findings, governments in France, Switzerland and the UK hurriedly set up studies near their own NPPs. All found leukemia increases but because their numbers were small the increases lacked “statistical significance”. That is, you couldn’t be 95% sure the findings weren’t chance ones.

This does not mean there were no increases, and indeed if less strict statistical tests had been applied, the results would have been “statistically significant”. But most people are easily bamboozled by statistics including scientists who should know better, and the strict 95% level tests were eagerly grasped by the governments wishing to avoid unwelcome findings. Indeed, many tests nowadays in this area use a 90% level.

In such situations, what you need to do is combine datasets in a meta-study to get larger numbers and thus reach higher levels of statistical significance. The four governments refrained from doing this because they knew what the answer would be, viz, statistically significant increases near almost all NPPs in the 4 countries. So Korblein and Fairlie helped them out by doing it for them (Korblein and Fairlie, 2012), and sure enough there were statistically significant increases near all the NPPs. Here are their findings-

Studies of observed (O) and expected (E) leukemia cases within 5 km of NPPs

O

E

SIR=O/E

90% CI

p-value

Germany

34

24.1

1.41

1.04-1.88

0.0328

Great Britain

20

15.4

1.30

0.86-1.89

0.1464

Switzerland

11

7.9a

1.40

0.78-2.31

0.1711

Franceb

14

10.2

1.37

0.83-2.15

0.1506

Pooled data

79

57.5

1.37

1.13-1.66

0.0042

a derived from data in Spycher et al. (2011).

b acute leukemia cases

This table reveals a highly statistically significant 37% increase in childhood leukemias within 5 km of almost all NPPs in the UK, Germany, France and Switzerland. It’s perhaps not surprising that the latter 3 countries have announced nuclear phaseouts and withdrawals. It is only the UK government that remains in denial.

So the matter is now beyond question, ie there’s a very clear association between increased child leukemias and proximity to NPPs. The remaining question is its cause(s).

Most people worry about radioactive emissions and direct radiation from the NPPs, however any theory involving radiation has a major difficulty to overcome, and that is how to account for the large (~10,000 fold) discrepancy between official dose estimates from NPP emissions and the clearly-observed increased risks.

My explanation does involve radiation. It stems from KiKK’s prinicipal finding that the increased incidences of infant and child leukemias were closely associated with proximity to the NPP chimneys. It also stems from KiKK’s observation that the increased solid cancers were mostly “embryonal”, ie babies were born either with solid cancers or with pre-cancerous tissues which, after birth, developed into full-blown tumours: this actually happens with leukemia as well.

My explanation has five main elements. First, the cancer increases may be due to radiation exposures from NPP emissions to air. Second, large annual spikes in NPP emissions may result in increased dose rates to populations within 5 km of NPPs. Third, the observed cancers may arise in utero in pregnant women. Fourth, both the doses and their risks to embryos and to fetuses may be greater than current estimates. And fifth, pre-natal blood-forming cells in bone marrow may be unusually radiosensitive. Together these five factors offer a possible explanation for the discrepancy between estimated radiation doses from NPP releases and the risks observed by the KIKK study. These factors are discussed in considerable detail in the full article.

My article in fact shows that the current discrepancy can be explained. The leukemia increases observed by KiKK and by many other studies may arise in utero as a result of embryonal/fetal exposures to incorporated radionuclides from NPP radioactive emissions. Very large emission spikes from NPPs might produce a pre-leukemic clone, and after birth a second radiation hit might transform a few of these clones into full-blown leukemia cells. The affected babies are born pre-leukemic (which is invisible) and the full leukemias are only diagnosed within the first few years after birth.

To date, no letters to the editor have been received pointing out errors or omissions in this article.

REFERENCES

Bithell JF, M F G Murphy, C A Stiller, E Toumpakari, T Vincent and R Wakeford. (2013) Leukaemia in young children in the vicinity of British nuclear power plants: a case–control study. Br J Cancer. advance online publication, September 12, 2013; doi:10.1038/bjc.2013.560.

Bunch KJ, T J Vincent1, R J Black, M S Pearce, R J Q McNally, P A McKinney, L Parker, A W Craft and M F G Murphy (2014) Updated investigations of cancer excesses in individuals born or resident in the vicinity of Sellafield and Dounreay. British Journal of Cancer (2014), 1–10 | doi: 10.1038/bjc.2014.357

Fairlie I (2013) A hypothesis to explain childhood cancers near nuclear power plants. Journal of Environmental Radioactivity 133 (2014) 10e17

Gardner MJ, Snee MP; Hall AJ; Powell CA; Downes S; Terrell JD (1990) Results of case-control study of leukaemia and lymphoma among young people near Sellafield nuclear plant in West Cumbria. BMJ. 1990;300:423–429.

Kaatsch P, Spix C, Schulze-Rath R, Schmiedel S, Blettner M. (2008) Leukaemia in young children living in the vicinity of German nuclear power plants. Int J Cancer; 122: 721-726.

Körblein A and Fairlie I (2012) French Geocap study confirms increased leukemia risks in young children near nuclear power plants. Int J Cancer 131: 2970–2971.

Spycher BD, Feller M, Zwahlen M, Röösli M, von der Weid NX, Hengartner H, Egger M, Kuehni CE. Childhood cancer and nuclear power plants in Switzerland: A census based cohort study. International Journal of Epidemiology (2011) doi:10.1093/ije/DYR115. http://ije.oxfordjournals.org/content/early/2011/07/11/ije.dyr115.full.pdf+html

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17 septembre 2014 3 17 /09 /septembre /2014 14:04
Tim Mousseau on genetic abnormalities in nature

August 15, 2014

The Ecosystem Are Being Slowly Revealed

http://www.businessinsider.com.au/the-serious-biological-effects-of-fukushima-radiation-on-plants-insects-and-animals-is-slowly-being-revealed-2014-8

Chris Pash Yesterday at 5:50 AM 421

Cattle graze in the distance at Masami Yoshizawa’s cattle farm where protest signs cover the landscape close to the devastated Fukushima plant. Masami Yoshizawa who runs the sanctuary, ‘Ranch of Hope’ for contaminated cattle, leads the movement among self-sacrificing farmers to protect cattle that were left behind in the exclusion zone in Fukushima after the nuclear disaster of Fukushima Daiichi Nuclear Power Plant following the earthquake and tsunami in March 11, 2011. (Photo by Paula Bronstein/Getty Images)

A range of scientific studies at Fukushima have begun to reveal the impact on the natural world from the radiation leaks at the power station in Japan caused by an earthquake and tsunami in 2011.

Biological samples were obtained only after extensive delays following the 1986 Chernobyl nuclear power plant meltdown, limiting the information which could be gained about the impact of that disaster.

Scientists, determined not to repeat the shortcomings of the Chernobyl studies, began gathering biological information only a few months after the meltdown of the Daiichi power plant in 2011.

Results of these studies are now beginning to reveal serious biological effects of the Fukushima radiation on non-human organisms ranging from plants to butterflies to birds.

A series of articles summarising these studies has now been published in the Journal of Heredity. These describe widespread impacts, ranging from population declines to genetic damage to responses by the repair mechanisms that help organisms cope with radiation exposure.

“A growing body of empirical results from studies of birds, monkeys, butterflies, and other insects suggests that some species have been significantly impacted by the radioactive releases related to the Fukushima disaster,” says Dr Timothy Mousseau of the University of South Carolina, lead author of one of the studies.

Common to all of the published studies is the hypothesis that chronic (low-dose) exposure to ionizing radiation results in genetic damage and increased mutation rates in reproductive and non-reproductive cells.

One of the studies documented the effects of radiation on rice by exposing healthy seedlings to low-level gamma radiation at a contaminated site in Fukushima Prefecture.

After three days, a number of effects were observed, including activation of genes involved in self-defense, ranging from DNA replication and repair to stress responses to cell death.

“The experimental design employed in this work will provide a new way to test how the entire rice plant genome responds to ionizing radiation under field conditions,” says Dr Randeep Rakwal of the University of Tsukuba in Japan, one of the authors of the study.

Another team of researchers examined the response of the pale grass blue butterfly, one of the most common butterfly species in Japan, to radiation exposure at the Fukushima site.

They found size reduction, slowed growth, high mortality and morphological abnormality both at the Fukushima site and among laboratory-bred butterflies with parents collected from the contaminated site.

“Non-contaminated larvae fed leaves from contaminated host plants collected near the reactor showed high rates of abnormality and mortality,” says Dr Joji Otaki of the University of the Ryukyus in Okinawa, Japan.

Some of their results suggested the possible evolution of radiation resistance in Fukushima butterflies as well.

This is a pale grass blue butterfly, one of the most common species of butterfly in Japan. Recent research has revealed major impacts on this species from the radiation leaks at the Fukushima nuclear power plant. Credit: Joji Otaki, University of the Ryukyus, Okinawa, Japan

A review of genetic and ecological studies for a range of other species at both Chernobyl and Fukushima (Mousseau 2014) revealed significant consequences of radiation. Population censuses of birds, butterflies, and cicadas at Fukushima showed major declines attributable to radiation exposure. Morphological effects, such as aberrant feathers on barn swallows, were also observed. The authors suggest that long-term studies at Chernobyl could predict likely effects in the future at the Fukushima site.

The scientists say there is an urgent need for greater investment in basic scientific research of the wild animals and plants of Fukushima.

Scientists detect genetic abnormalities in Fukushima birds, insects

http://www.japantimes.co.jp/news/2014/08/15/national/science-health/japan-u-s-warn-of-species-mutations-in-fukushima/#.U-78KmOnq1v

Kyodo

WASHINGTON – In a set of papers published Thursday in the Journal of Heredity, a U.S. publication, Japanese and U.S. scientists warned that radioactive materials released from by the core meltdowns at the Fukushima No. 1 power plant could have caused abnormalities in the genes of nearby birds and insects.

In a paper published on the journal’s website, Mousseau said barn swallows with abnormal white spots on their plumage were found near the Chernobyl plant after the disaster and that the discovery of similarly plumaged swallows in Fukushima was also reported in the wake of the 2011 crisis.

“Barn swallows with aberrant white feathers were first detected in Fukushima in 2012 and were observed in increasing frequencies in 2013 and 2014,” the paper said.

Mousseau is closely watching for signs of population decline in some birds due to abnormalities in mitochondrial DNA in areas near the Fukushima plant, since the same problem was reported in Chernobyl.

The poorly protected and maintained Fukushima plant, operated by Tokyo Electric Power Co., was extensively damaged by tsunami spawned by the Great East Japan Earthquake in March 2011 and suffered a blackout after losing its cooling systems.

High concentrations of radioactive materials spewed in the world’s worst nuclear accident since Chernobyl forced thousands of residents in Fukushima and elsewhere to flee.

Joji Otaki, associate professor at the University of the Ryukyus in Okinawa Prefecture, said in a separate paper in the same journal that abnormalities in the genes and sizes of pale grass blue butterflies were also detected. They were captured near the Fukushima plant.

Otaki said the abnormality rate for the butterfly, common in many parts of Japan, declined after peaking in September 2011 and that the finding could suggest the species possibly adjusted itself to the new environment and acquired radiation resistance after the meltdowns.

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Published by fukushima-is-still-news - dans Health effects of radiation
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9 septembre 2014 2 09 /09 /septembre /2014 17:05

August 15, 2014

The Ecosystem Are Being Slowly Revealed

http://www.businessinsider.com.au/the-serious-biological-effects-of-fukushima-radiation-on-plants-insects-and-animals-is-slowly-being-revealed-2014-8

Chris Pash Yesterday at 5:50 AM 421

Cattle graze in the distance at Masami Yoshizawa’s cattle farm where protest signs cover the landscape close to the devastated Fukushima plant. Masami Yoshizawa who runs the sanctuary, ‘Ranch of Hope’ for contaminated cattle, leads the movement among self-sacrificing farmers to protect cattle that were left behind in the exclusion zone in Fukushima after the nuclear disaster of Fukushima Daiichi Nuclear Power Plant following the earthquake and tsunami in March 11, 2011. (Photo by Paula Bronstein/Getty Images)

A range of scientific studies at Fukushima have begun to reveal the impact on the natural world from the radiation leaks at the power station in Japan caused by an earthquake and tsunami in 2011.

Biological samples were obtained only after extensive delays following the 1986 Chernobyl nuclear power plant meltdown, limiting the information which could be gained about the impact of that disaster.

Scientists, determined not to repeat the shortcomings of the Chernobyl studies, began gathering biological information only a few months after the meltdown of the Daiichi power plant in 2011.

Results of these studies are now beginning to reveal serious biological effects of the Fukushima radiation on non-human organisms ranging from plants to butterflies to birds.

A series of articles summarising these studies has now been published in the Journal of Heredity. These describe widespread impacts, ranging from population declines to genetic damage to responses by the repair mechanisms that help organisms cope with radiation exposure.

“A growing body of empirical results from studies of birds, monkeys, butterflies, and other insects suggests that some species have been significantly impacted by the radioactive releases related to the Fukushima disaster,” says Dr Timothy Mousseau of the University of South Carolina, lead author of one of the studies.

Common to all of the published studies is the hypothesis that chronic (low-dose) exposure to ionizing radiation results in genetic damage and increased mutation rates in reproductive and non-reproductive cells.

One of the studies documented the effects of radiation on rice by exposing healthy seedlings to low-level gamma radiation at a contaminated site in Fukushima Prefecture.

After three days, a number of effects were observed, including activation of genes involved in self-defense, ranging from DNA replication and repair to stress responses to cell death.

“The experimental design employed in this work will provide a new way to test how the entire rice plant genome responds to ionizing radiation under field conditions,” says Dr Randeep Rakwal of the University of Tsukuba in Japan, one of the authors of the study.

Another team of researchers examined the response of the pale grass blue butterfly, one of the most common butterfly species in Japan, to radiation exposure at the Fukushima site.

They found size reduction, slowed growth, high mortality and morphological abnormality both at the Fukushima site and among laboratory-bred butterflies with parents collected from the contaminated site.

“Non-contaminated larvae fed leaves from contaminated host plants collected near the reactor showed high rates of abnormality and mortality,” says Dr Joji Otaki of the University of the Ryukyus in Okinawa, Japan.

Some of their results suggested the possible evolution of radiation resistance in Fukushima butterflies as well.

This is a pale grass blue butterfly, one of the most common species of butterfly in Japan. Recent research has revealed major impacts on this species from the radiation leaks at the Fukushima nuclear power plant. Credit: Joji Otaki, University of the Ryukyus, Okinawa, Japan

A review of genetic and ecological studies for a range of other species at both Chernobyl and Fukushima (Mousseau 2014) revealed significant consequences of radiation. Population censuses of birds, butterflies, and cicadas at Fukushima showed major declines attributable to radiation exposure. Morphological effects, such as aberrant feathers on barn swallows, were also observed. The authors suggest that long-term studies at Chernobyl could predict likely effects in the future at the Fukushima site.

The scientists say there is an urgent need for greater investment in basic scientific research of the wild animals and plants of Fukushima.

Scientists detect genetic abnormalities in Fukushima birds, insects

http://www.japantimes.co.jp/news/2014/08/15/national/science-health/japan-u-s-warn-of-species-mutations-in-fukushima/#.U-78KmOnq1v

Kyodo

WASHINGTON – In a set of papers published Thursday in the Journal of Heredity, a U.S. publication, Japanese and U.S. scientists warned that radioactive materials released from by the core meltdowns at the Fukushima No. 1 power plant could have caused abnormalities in the genes of nearby birds and insects.

In a paper published on the journal’s website, Mousseau said barn swallows with abnormal white spots on their plumage were found near the Chernobyl plant after the disaster and that the discovery of similarly plumaged swallows in Fukushima was also reported in the wake of the 2011 crisis.

“Barn swallows with aberrant white feathers were first detected in Fukushima in 2012 and were observed in increasing frequencies in 2013 and 2014,” the paper said.

Mousseau is closely watching for signs of population decline in some birds due to abnormalities in mitochondrial DNA in areas near the Fukushima plant, since the same problem was reported in Chernobyl.

The poorly protected and maintained Fukushima plant, operated by Tokyo Electric Power Co., was extensively damaged by tsunami spawned by the Great East Japan Earthquake in March 2011 and suffered a blackout after losing its cooling systems.

High concentrations of radioactive materials spewed in the world’s worst nuclear accident since Chernobyl forced thousands of residents in Fukushima and elsewhere to flee.

Joji Otaki, associate professor at the University of the Ryukyus in Okinawa Prefecture, said in a separate paper in the same journal that abnormalities in the genes and sizes of pale grass blue butterflies were also detected. They were captured near the Fukushima plant.

Otaki said the abnormality rate for the butterfly, common in many parts of Japan, declined after peaking in September 2011 and that the finding could suggest the species possibly adjusted itself to the new environment and acquired radiation resistance after the meltdowns.

Cattle graze in the distance at Masami Yoshizawa’s cattle farm where protest signs cover the landscape close to the devastated Fukushima plant. Masami Yoshizawa who runs the sanctuary, ‘Ranch of Hope’ for contaminated cattle, leads the movement among self-sacrificing farmers to protect cattle that were left behind in the exclusion zone in Fukushima after the nuclear disaster of Fukushima Daiichi Nuclear Power Plant following the earthquake and tsunami in March 11, 2011. (Photo by Paula Bronstein/Getty Images)

A range of scientific studies at Fukushima have begun to reveal the impact on the natural world from the radiation leaks at the power station in Japan caused by an earthquake and tsunami in 2011.

Biological samples were obtained only after extensive delays following the 1986 Chernobyl nuclear power plant meltdown, limiting the information which could be gained about the impact of that disaster.

Scientists, determined not to repeat the shortcomings of the Chernobyl studies, began gathering biological information only a few months after the meltdown of the Daiichi power plant in 2011.

Results of these studies are now beginning to reveal serious biological effects of the Fukushima radiation on non-human organisms ranging from plants to butterflies to birds.

A series of articles summarising these studies has now been published in the Journal of Heredity. These describe widespread impacts, ranging from population declines to genetic damage to responses by the repair mechanisms that help organisms cope with radiation exposure.

“A growing body of empirical results from studies of birds, monkeys, butterflies, and other insects suggests that some species have been significantly impacted by the radioactive releases related to the Fukushima disaster,” says Dr Timothy Mousseau of the University of South Carolina, lead author of one of the studies.

Common to all of the published studies is the hypothesis that chronic (low-dose) exposure to ionizing radiation results in genetic damage and increased mutation rates in reproductive and non-reproductive cells.

One of the studies documented the effects of radiation on rice by exposing healthy seedlings to low-level gamma radiation at a contaminated site in Fukushima Prefecture.

After three days, a number of effects were observed, including activation of genes involved in self-defense, ranging from DNA replication and repair to stress responses to cell death.

“The experimental design employed in this work will provide a new way to test how the entire rice plant genome responds to ionizing radiation under field conditions,” says Dr Randeep Rakwal of the University of Tsukuba in Japan, one of the authors of the study.

Another team of researchers examined the response of the pale grass blue butterfly, one of the most common butterfly species in Japan, to radiation exposure at the Fukushima site.

They found size reduction, slowed growth, high mortality and morphological abnormality both at the Fukushima site and among laboratory-bred butterflies with parents collected from the contaminated site.

“Non-contaminated larvae fed leaves from contaminated host plants collected near the reactor showed high rates of abnormality and mortality,” says Dr Joji Otaki of the University of the Ryukyus in Okinawa, Japan.

Some of their results suggested the possible evolution of radiation resistance in Fukushima butterflies as well.

This is a pale grass blue butterfly, one of the most common species of butterfly in Japan. Recent research has revealed major impacts on this species from the radiation leaks at the Fukushima nuclear power plant. Credit: Joji Otaki, University of the Ryukyus, Okinawa, Japan

A review of genetic and ecological studies for a range of other species at both Chernobyl and Fukushima (Mousseau 2014) revealed significant consequences of radiation. Population censuses of birds, butterflies, and cicadas at Fukushima showed major declines attributable to radiation exposure. Morphological effects, such as aberrant feathers on barn swallows, were also observed. The authors suggest that long-term studies at Chernobyl could predict likely effects in the future at the Fukushima site.

The scientists say there is an urgent need for greater investment in basic scientific research of the wild animals and plants of Fukushima.

Impact of radiation on living things

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Published by fukushima-is-still-news - dans Health effects of radiation
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25 août 2014 1 25 /08 /août /2014 17:13

August 25, 2014

More thyroid cancer cases reported in Fukushima Pref. health survey

http://mainichi.jp/english/english/newsselect/news/20140825p2a00m0na005000c.html

An ongoing health survey of Fukushima Prefecture residents conducted in the wake of the Fukushima nuclear disaster has uncovered seven new cases of thyroid cancer among people who were aged 18 or under when the disaster broke out in March 2011.

The new cases reported since the previous announcement in May bring the total number of thyroid cancer cases among prefectural residents in this age group to 57. Including suspected cases, the figure rose by 14 to 103.

Fukushima Medical University, which is in charge of the health survey, says it is unlikely that these young people developed cancer as a result of exposure to radiation, as there was little variance in the rate of cases among different districts, and because there were few cases among children aged 5 and under, who are more susceptible to the effects of radiation exposure.

The new cases were reported at a health survey committee meeting in the city of Fukushima on Aug. 24.

A breakdown of data from four districts of the prefecture showed little variance in the rate of occurrence between three of the districts: 13 municipalities including areas designated as evacuation zones after the outbreak of the nuclear disaster at Tokyo Electric Power Co.'s Fukushima No. 1 Nuclear Power Plant; the Hamadori district including the city of Iwaki; and the Nakadori district extending to the cities of Fukushima and Koriyama. In these districts, the rate averaged 33.5 to 36.4 cases per 100,000 people. In the Aizu district, the average was lower, at 27.7 per 100,000, but officials suspect this is due to the fact that thyroid testing in this district has not progressed.

August 24, 2014

Thyroid cancer diagnosed in 104 young people in Fukushima

http://ajw.asahi.com/article/0311disaster/fukushima/AJ201408240011

By YURI OIWA/ Staff Writer

The number of young people in Fukushima Prefecture who have been diagnosed with definitive or suspected thyroid gland cancer, a disease often caused by radiation exposure, now totals 104, according to prefectural officials.

The 104 are among 300,000 young people who were aged 18 or under at the time of the 2011 Fukushima nuclear disaster and whose results of thyroid gland tests have been made available as of June 30. They were eligible for the tests administered by the prefectural government.

Of these 104, including 68 women, the number of definitive cases is 57, and one has been diagnosed with a benign tumor. The size of the tumors varies from 5 to 41 millimeters and averages 14 mm.

The average age of those diagnosed was 14.8 when the Great East Japan Earthquake and tsunami triggered the meltdowns at the Fukushima No. 1 nuclear power plant in March 2011.

However, government officials in Fukushima say they do not believe the cases of thyroid gland cancer diagnosed or suspected in the 104 young people are linked to the 2011 nuclear accident.

The figure can be extrapolated for comparison purposes to an average of more than 30 people per population of 100,000 having definitive or suspected thyroid gland cancer.

The figure is much higher than, for example, the development rate of thyroid cancer of 1.7 people per 100,000 among late teens based on the cancer patients’ registration in Miyagi Prefecture.

But experts say the figures cannot be compared because the test in Fukushima Prefecture covers a large number of people who have no symptoms.

Experts are divided over whether the cases of thyroid gland cancer diagnosed or suspected in the 104 young people should be linked to the 2011 nuclear accident.

In connection with the 1986 Chernobyl disaster, the number of young people diagnosed with thyroid cancer rose only after four years. The cancer is also known to develop slowly.

But some researchers say that the occurrence of thyroid gland cancer is likely to be increased by the Fukushima nuclear accident.

“Many people are being diagnosed with cancer at this time, thanks to the high-precision tests,” said Yoshio Hosoi, professor of radiation biology at Tohoku University. “We must continue closely examining the people’s health in order to determine the impact of radiation exposure on causing thyroid tumors.”

By regions, 27.7 people per 100,000 people have been diagnosed with definitive or suspected thyroid cancer in the Aizu region, located 80 kilometers or farther from the crippled nuclear plant. The number could increase after thorough examinations are completed for people in the region

Around 35 people per 100,000 have been diagnosed with definitive or suspected cancer in the Nakadori region, which includes Fukushima city and several municipalities designated as mandatory evacuation zones, and the coastal Hamadori region.

Hokuto Hoshi, who chairs a panel that discusses matters related to the prefectural survey on the health impact from radiation on Fukushima’s residents, said the panel’s subcommittee will soon analyze the test results to determine the impact of the accident on the thyroid tumor rate.

“In order to scientifically compare the results of the development rates of each region, we must take into account age and other characteristics (of the 104 people),” he said.

The prefecture also plans to continue medical checkups on residents in the prefecture and use the test results as a basis for comparison in the future, prefectural officials said.

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9 août 2014 6 09 /08 /août /2014 21:21

August 8, 2014

Bikini Atoll nuclear test exposed fisherman to radiation level equivalent to Hiroshima

http://mainichi.jp/english/english/newsselect/news/20140808p2a00m0na008000c.html 

 

A fisherman around 1,300 kilometers from a United States nuclear bomb test site at the Bikini Atoll in 1954 was affected by a radiation amount about the same as being 1.6 kilometers from the Hiroshima atomic bomb hypocenter, according to research results.


The findings were revealed by professor Shin Toyoda of Okayama University of Science at a meeting of experts on Aug. 7. Toyoda's research group used technology called "electron spin resonance" to measure the number of unpaired electrons in the enamel of two molars and one canine tooth provided by two men on fishing boats exposed to the Bikini Atoll nuclear test.


Toyoda says the researchers took advantage of the fact that unlike in cells, digestion does not occur in tooth enamel, so the effects of radiation exposure remain unaltered. They found evidence of up to 414 millisieverts of radiation exposure from the nuclear test from the enamel of a Kochi Prefecture man in his 80s. The other man was found to have been exposed to up to 252 millisieverts. The researchers accounted for additional radiation exposure over the years from sources like medical x-rays.


The research group was put together at the urging of Hiroshima University's professor emeritus Masaharu Hoshi. It aims to uncover information about the Bikini Atoll nuclear test by researching official documents as well as the teeth and chromosomal abnormalities of people who were on boats exposed to the radiation. The group is continuing to ask for teeth from exposed people for further research.


August 08, 2014(Mainichi Japan)

 

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31 juillet 2014 4 31 /07 /juillet /2014 22:21

 July 31, 2014

Gov't raises max allowable ambient radiation level in nuclear disaster cleanup zones

http://mainichi.jp/english/english/newsselect/news/20140731p2a00m0na022000c.html 

 

The government will raise the maximum ambient radiation level target for the cleanup operation around the stricken Fukushima No. 1 nuclear plant from an hourly 0.23 microsieverts to 0.3-0.6 microsieverts.


The Environment Ministry made the decision after analysis showing that people living in contaminated zones would still have an annual dose of less than the 1 millisievert maximum even at the new, higher hourly target. While relaxing the 0.23 microsievert hourly maximum (which does not include normal background radiation) will make the cleanup operation more efficient, residents of the municipalities affected may find the sudden shift upwards of the "safe" dose worrying.


The ministry will present the revised number to municipalities concerned at a meeting sometime soon. At the same time, the government will present a plan to distribute dosimeters to residents to track their individual doses. Individual exposure varies depending on the person's location and their daily activities, and the ministry plans to use this detailed data to adjust the intensity of the cleanup operations to best suit local conditions and focus on areas of the most need.


In short, the government is looking to shift away from the blanket cleanup operation of the past three years to prioritizing reducing the radiation doses of residents.


Environment Ministry guidelines issued for the cleanup areas in 2011 advised residents to stay indoors 16 hours a day, adding that the dose absorbed inside a wooden structure was 40 percent of that when in the open air. The ministry also stated that it had calculated the maximum hourly ambient radiation level at 0.23 microsieverts for residents to stay under the prescribed 1 millisievert per year dose.


Based on the ministry advisory, the cities of Fukushima, Koriyama and other local bodies drew up plans to clear away contaminated soil to get the radiation level below the 0.23 microsievert per hour mark. Authorities discovered, however, that the lower the radioactive contamination in a particular spot, the less effective was the cleanup operation in getting rid of it. There have been many cases where radiation levels have remained stubbornly above 0.23 microsieverts per hour even after decontamination, sparking resident demands that cleanups be repeated.


The cities of Date and Soma, meanwhile, distributed dosimeters to their residents in affected areas, and compared ambient radiation levels with the actual doses absorbed by their citizens. Environment Ministry analysis of the data showed that residents living in areas with an ambient radiation level of 0.3-0.6 microsieverts per hour for the most part stayed under the maximum annual dose of 1 millisievert.


With these results in hand, the ministry declared that it was "necessary to respond to the actual situation with respect to resident's radiation dose levels" and embarked on the policy shift.

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31 juillet 2014 4 31 /07 /juillet /2014 20:45

 July 31, 2014

 

n-thyroidcancer-a-20140801-870x581-copie-1.jpg

 

A doctor conducts a thyroid examination on a 5-year-old girl at a clinic in a temporary housing complex in Nihonmatsu, Fukushima Prefecture, in February. | REUTERS

Experts worry that radiation fears are leading to unnecessary surgery for children

Experts question Fukushima thyroid screening

by Mizuho Aoki 

http://www.japantimes.co.jp/news/2014/07/31/national/science-health/experts-question-fukushima-thyroid-screening/#.U9ozyGPi91s 

 

More than three years after the triple core meltdown in Fukushima Prefecture devastated the lives of thousands of residents, the effect that the radiation release is having on children’s thyroid glands still weighs heavily on residents’ minds.


The iodine-131 released into the air by the meltdowns accumulates in the thyroid gland, increasing the risk of thyroid cancer. The gland is responsible for regulating hormone levels in the body.


Children are considered especially vulnerable. After the 1986 Chernobyl disaster, more than 6,000 children were diagnosed with thyroid cancer by 2005, according to the U.N. Scientific Committee of the Effects of Atomic Radiation.

Given the local anxiety, the Fukushima Prefectural Government in October 2011 started offering free thyroid screenings for everyone who was 18 or younger at the time of the disaster. The prefecture has 370,000 residents in that age group, and 300,000 had received voluntary checkups by the end of March.


The program may look good on paper, but it has drawn flak from medical experts who say it is far from adequate in determining a link between the cancers found and radiation exposure.


At the core of the criticism is the prefectural government’s policy of not releasing data on the results of the checkups, such as what stage of cancer the examinees are in.


This lack of disclosure — based on prefectural privacy policies — has made it hard for experts to accurately judge whether the abnormally high incidence of thyroid cancer in Fukushima is being caused the nuclear debacle or the higher screening rate.


In addition, the prefecture has no authority to follow up on children who test positive for cancer, meaning its data on the medical effects of the aftermath of the disaster will be limited.


As of March, the prefectural government found 90 children with suspected thyroid cancer after nearly 300,000 examinations. The prefecture was able to confirm that 51 of them opted to have surgery to remove part or all of their thyroid gland.


This figure is clearly high compared with a thyroid cancer registry rate of around one to nine per 1 million teens in Japan, experts say.


But because thyroid cancer often causes no symptoms and thus goes undiagnosed, experts point to the possibility that the ratio in Fukushima has turned out to be higher simply due to the widespread screening.


“The screenings may have ended up finding cancer that would have never have caused a health problem for their entire lives even if left unattended,” said Kenji Shibuya, a professor and chairman of the department of global health policy at the University of Tokyo.


The thyroid cancer rate among children near the Chernobyl plant started to rise four to five years after the catastrophe, mainly because they kept drinking highly contaminated milk and local produce, according to UNSCEAR.


But in Fukushima, several studies have confirmed that internal and external exposure levels were indeed much lower than those around the former Soviet power plant, which met a much more violent fate.


In April, UNSCEAR said that in Fukushima “the occurrence of a large number of radiation-induced thyroid cancers as were observed after Chernobyl can be discounted because doses were substantially lower.”


“Given the low radiation exposure levels, it is possible that detected cancers were the kind of cancers that would never do harm. But they were found because of the screenings,” said Shibuya, a member of a panel tasked with assessing the result of the thyroid examinations in Fukushima.


He added that there is also a possibility that patients underwent unnecessary surgery.


To examine the possibility of overdiagnosis— diagnosis of a malady that never causes symptoms or death — Shibuya and other medical experts have urged Fukushima Medical University, which is heading up the examination program, to disclose its findings on treated patients, such as the percentage of thyroid cancer cases that spread to the lymph nodes or elsewhere in the body.


The university refuses to disclose the data for privacy reasons.


The Fukushima Prefectural Government meanwhile says it doesn’t have the authority to track down and gather the information from medical institutions because treatment after diagnosis is outside its jurisdiction.


Fukushima official Yukio Kakuta acknowledged that the prefecture can’t track down all patients.


“Under the current system, we can’t follow up on all of the patients,” Kakuta said. “In addition to the issue of privacy, it’s my understanding that some patients and their parents are skeptical of the prefecture-led health checkup program itself, and that some people don’t trust Fukushima Medical University.


“I believe some of those people have gone to other hospitals to get their thyroid glands checked and treated,” which makes it difficult for the prefecture to find out what happens to them over the long term, he said.


Kakuta said the information disclosure issue will be discussed at the next meeting of a local committee in late August but will stay in place for now.


Shibuya of the University of Tokyo pointed out that the disclosure of information on the stages of the cancers does not violate patient privacy.


“They only have to disclose information on percentages of various cancer stages, such as the cases when the lymph nodes are infiltrated with malignant cells,” he said.


“If all of the treated cancers were such cases, then we would know (what’s happening in Fukushima) is not normal, and start discussions on the potential effects of the radiation,” he said. “But without disclosing the data, the suspicion (of overdiagnosis) will never go away.”


With the spreading use of sonography, overdiagnosis of thyroid cancer has become a concern worldwide. While the number of cases is on the rise, experts say the mortality rate remains unchanged.


Papillary thyroid cancer, the type that appears most prevalent among children in Fukushima, is known for having a slow growth rate and very low risk of death, the experts say. Therefore, many hospitals in Japan nowadays tell patients that long-term observation of their condition is an option to surgery.


Iwao Sugitani, a professor and chairman of the department of endocrine surgery at Nippon Medical School Graduate School of Medicine, said about 90 percent of thyroid cancer cases in Japan involve papillary thyroid cancer. While around nine out of every 10 patients with this type of cancer face no immediate threat to their lives, experts are divided on whether to perform surgery in such cases.


According to a study conducted by the Cancer Institute Hospital in Tokyo from 1995 to 2009, a total of 283 papillary thyroid cancer patients chose not to have surgery and opted instead to be monitored on a regular basis. None died nor saw the cancer spread, according to the study.


“Early detection and early treatment is recommendable for most cancers. But I don’t see much meaning in finding and conducting surgery on people with a small papillary thyroid cancer that would go undetected for their entire lifetimes” without screening, Sugitani said.


Shibuya of the University of Tokyo also questions whether the mostly benign nature of papillary thyroid cancer and the option of having no surgery are being fully explained to the children and their parents in Fukushima.


“Without such knowledge, it’s natural for most parents to ask doctors to perform surgery,” Shibuya said.


By going under the knife, “children will have scars on their necks, and they may suffer from the thought that they developed cancer due to radiation exposure,” he said. “Some of them might have to take hormone tablets during their entire lives. (The Fukushima government) must think harder on whether it should continue the program as it is now.”

 

 

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