01 /29 2013

Even low-level radioactivity is damaging

Broad analysis of many radiation studies finds no exposure threshold that precludes harm to life

By Steven Powell, spowell2@mailbox.sc.edu, 803-777-1923


Even the very lowest levels of radiation are harmful to life, scientists have concluded in the Cambridge Philosophical Society’s journal Biological Reviews. Reporting the results of a wide-ranging analysis of 46 peer-reviewed studies published over the past 40 years, researchers from the University of South Carolina and the University of Paris-Sud found that variation in low-level, natural background radiation had small, but highly statistically significant, negative effects on DNA as well as several measures of health.

The review is a meta-analysis of studies of locations around the globe that have very high natural background radiation as a result of the minerals in the ground there, including Ramsar, Iran, Mombasa, Kenya, Lodeve, France, and Yangjiang, China. These, and a few other geographic locations with natural background radiation that greatly exceeds normal amounts, have long drawn scientists intent on understanding the effects of radiation on life. Individual studies by themselves, however, have often only shown small effects on small populations from which conclusive statistical conclusions were difficult to draw.

“When you’re looking at such small effect sizes, the size of the population you need to study is huge,” said co-author Timothy Mousseau, a biologist in the College of Arts and Sciences at the University of South Carolina. “Pooling across multiple studies, in multiple areas, and in a rigorous statistical manner provides a tool to really get at these questions about low-level radiation.”

Mousseau and co-author Anders Møller of the University of Paris-Sud combed the scientific literature, examining more than 5,000 papers involving natural background radiation that were narrowed to 46 for quantitative comparison. The selected studies all examined both a control group and a more highly irradiated population and quantified the size of the radiation levels for each. Each paper also reported test statistics that allowed direct comparison between the studies.

The organisms studied included plants and animals, but had a large preponderance of human subjects. Each study examined one or more possible effects of radiation, such as DNA damage measured in the lab, prevalence of a disease such as Down’s Syndrome, or the sex ratio produced in offspring. For each effect, a statistical algorithm was used to generate a single value, the effect size, which could be compared across all the studies.

The scientists reported significant negative effects in a range of categories, including immunology, physiology, mutation and disease occurrence. The frequency of negative effects was beyond that of random chance.

“There’s been a sentiment in the community that because we don’t see obvious effects in some of these places, or that what we see tends to be small and localized, that maybe there aren’t any negative effects from low levels of radiation,” said Mousseau. “But when you do the meta-analysis, you do see significant negative effects.”

“It also provides evidence that there is no threshold below which there are no effects of radiation,” he added. “A theory that has been batted around a lot over the last couple of decades is the idea that is there a threshold of exposure below which there are no negative consequences. These data provide fairly strong evidence that there is no threshold – radiation effects are measurable as far down as you can go, given the statistical power you have at hand.”

Mousseau hopes their results, which are consistent with the “linear-no-threshold” model for radiation effects, will better inform the debate about exposure risks. “With the levels of contamination that we have seen as a result of nuclear power plants, especially in the past, and even as a result of Chernobyl and Fukushima and related accidents, there’s an attempt in the industry to downplay the doses that the populations are getting, because maybe it’s only one or two times beyond what is thought to be the natural background level,” he said. “But they’re assuming the natural background levels are fine.”

“And the truth is, if we see effects at these low levels, then we have to be thinking differently about how we develop regulations for exposures, and especially intentional exposures to populations, like the emissions from nuclear power plants, medical procedures, and even some x-ray machines at airports.”
















01 /25 2013

Fishermen find what could be tsunami debris off Kona coast







Related articleBoat brought into Honokohau Harbor is a possible Japan tsunami debris


"The state Department of Health has been contacted regarding a testing for radiation levels."

Hawaii Tsunami Debris: Fridge Parts And Oyster Buoys From Japan Wash Ashore On Oahu And Kauai

Posted: 01/18/2013 9:05 am EST

From Stephanie Pappas, LiveScience Senior Writer:

Oyster buoys and refrigerator parts set adrift by the 2011 Japan tsunami are now rolling in with the tide on Hawaii's beaches, a new field survey reveals.


Black oyster buoys and refrigerator parts — and even a full refrigerator — that trace back to Japan have shown up on the islands of Oahu and Kauai, said Nicholas Mallos, a conservation biologist and ocean debris specialist at the nonprofit Ocean Conservancy. Also on Oahu, researchers found a large 4-foot by 4-foot (1.2 by 1.2 meters) chunk of housing insulation framed in wood, a piece almost certainly sent into the sea by the devastating tsunami.

"These items have never before been seen on these beaches," Mallos told LiveScience.

The Japanese government has estimated the tsunami, which was triggered by an underwater earthquake in March 2011, swept about 5 million tons of wreckage out to sea. While 70 percent appears to have sunk offshore, the rest is floating in the Pacific Ocean. The first bit to show up in Hawaii, in September, was a barnacle-covered seafood storage bin.


Paradise of plastic

Exposed to ocean currents on every side, the Hawaiian Islands are a hotspot for Pacific junk. Some of this ocean litter originates from the fishing industry; most of the rest is consumer garbage from soda bottles, toys and other plastic goods, much broken down by the waves beyond recognition. [In Photos: Tsunami Debris & Ocean Trash in Hawaii]

At Kimalo Point on Hawaii's Big Island, tiny fragments of plastic penetrate as much as 3 feet (0.9 meters) below the beach surface.


"Many places on the beach, it's hard to differentiate the sand from the plastics on the surface," Mallos said.

The tsunami debris is different. For one thing, it tends to be larger, having only been in the ocean since March 2011, Mallos said. The debris also comes ashore in surprisingly homogenous waves. This summer, it was oyster buoys, Mallos said. Now, it's refrigerator parts.

The reason? Wind acts on similar objects in similar ways, according to research by Nikolai Maximenko of the University of Hawaii at Manoa's International Pacific Research Center. All of the tsunami debris went into the ocean at the same time, but some objects drift across the Pacific faster than others. That results in clusters of similar objects showing up in Hawaii and along the North American West Coast at the same time. [Tracking Tsunami Debris (Infographic)]

Debris hunt

Mallos and colleagues from the Japan Environmental Action Network, the Oceanic Wildlife Survey and the Japan Ministry of the Environment just completed a beach survey in Hawaii in search of this tsunami debris. They found about six or seven items, including the rusted Japanese refrigerator and buoys, which very likely came from the tsunami, Mallos said.

"We're not seeing a massive wave of debris wash onto the shore at one time, but right now, what it's been is a slow accumulation of debris here and there," he said.

The tsunami debris is a problem, but it's part of a much bigger issue, Mallos said. Hawaii is awash with plastic trash from all over the world; the islands also neighbor the Great Pacific Garbage Patch, an area of the North Pacific where currents push masses of plastics into a suspended gyre of trash. Long story short: The oceans are a mess.

The Hawaii survey turned up masses of this typical ocean garbage, including fishing nets and traps, Mallos said. One of the stranger items was an intact plastic trashcan from Los Angeles County with "Heal the Bay" stickers on it. Heal the Bay is a nonprofit group that works to clean up California's Santa Monica Bay. In an unfortunate irony, one of the group's trashcans got into the ocean and floated some 2,500 miles (4,023 kilometers) to end up on a beach in Hawaii.

"It really highlights the fact that trash travels very far," Mallos said.

The average person can do their part to reduce ocean trash, Mallos said. Because consumer plastics are a huge part of the problem, resolving to use reusable grocery bags, coffee mugs and water bottles can keep one-time use plastics out of the oceans. The Ocean Conservancy has developed a free app, called Rippl, designed to nudge users into a more ocean-friendly routine by reminding them to take those sorts of small actions.

Click picture for the link.

The problem of typical ocean trash is inextricably linked to the issue of tsunami debris, Mallos said. Tsunamis aren't preventable, but regular ocean litter is, he said.

"To the extent we can keep regular forms of ocean trash out of the ocean, in the face of disasters, the ocean becomes more resilient and better equipped to deal with the debris," he said.

The new survey was funded by the Environmental Restoration and Conservation Agency of Japan.












忘却の彼方の神風福島50 in JAPAN

01 /20 2013


Fukushima 50: 'We felt like kamikaze pilots ready to sacrifice everything'
福島50: 「全てを犠牲にする事を覚悟した神風特攻隊のようだと感じた」

Nuclear plant staff live unseen in the shadow of the disaster, says worker Atsufumi Yoshizawa, as Japan grapples with the fallout from the world's worst nuclear accident since Chernobyl

Justin McCurry in Tokyo

guardian.co.uk, Friday 11 January 2013 13.11 GMT

Dressed in a dark-blue work jacket with his company motif stamped on his breast pocket, Atsufumi Yoshizawa does not look like a man who spent the best part of a year in the thick of battle.

Yet that is how he describes his time among the group of engineers, technicians, soldiers and firefighters who risked their lives to remain at the heart of Japan's worst nuclear crisis.

The international media named them the Fukushima 50, although the actual number of workers who stayed to handle the triple meltdown at Fukushima Daiichi nuclear plant ran into the hundreds.

control room
The Fukushima No 1 nuclear power plant control room. Jolts from an earthquake caused ceiling panels to crash to the floor. Photograph: AFP/Getty Images

They became the heroes of the disaster. The world feted their bravery and selfless dedication, an antidote to the opprobrium being poured on Japan's hapless nuclear safety officials and politicians. But at home, almost all of the Fukushima 50 have remained anonymous. Some shun the spotlight, but many others fear reprisals as the public continues to grapple with the environmental and political fallout from the world's worst nuclear disaster since Chernobyl.

In a rare interview, Yoshizawa describes how the crisis unfolded, and why he does not consider himself a hero.

atsufumi yoshizawa
Atsufumi Yoshizawa, a member of the Fukushima 50 who was in charge of two reactors at Fukushima Daiichi. Photograph: Tokyo Electric Power Company

When Japan's north-east coast was shaken by a magnitude 9.0 earthquake on the afternoon of 11 March 2011, Yoshizawa was certain of two things: he would not flee, and he would not die.

The 54-year-old nuclear engineer was about to end his shift at Fukushima Daiichi when the first powerful jolt arrived. Violent swaying ensued, causing panels to crash from the ceiling. Yoshizawa, who was in a corridor outside the plant's main control room, was forced to crouch on the floor before talking shelter beneath a desk.

"I managed to look out of a window and saw parked cars bouncing up and down from the sheer force of the earthquake. I had never experienced anything like it," he said in a recent interview at the headquarters of the plant's operator, the Tokyo Electric Power Company (Tepco).

Yoshizawa, who joined the company straight from university 30 years ago, was one of 6,000 workers on site that afternoon, a third of them in the restricted area near the plant's six reactors. His immediate thoughts were not with his wife and two daughters, who he assumed were safe at home in Yokohama, south of Tokyo, but with his colleagues, most of whom had families living near the plant.


Once the shaking had subsided, Yoshizawa, a slight, bespectacled man who has swapped his anti-radiation suit for a shirt and tie since his transfer last year to the Tepco headquarters, where he is general manager of the nuclear fuel cycle department, headed to an earthquake-proof room where senior staff had gathered to discuss their response.

It was there, less than an hour after the quake, that news began to circulate that the plant had been struck by a tsunami much bigger than the 3-metre wave predicted in news bulletins – and far higher than the facility's protective seawall had been built to withstand.

The evacuation building had no windows, so none of the men inside could see the tsunami as it ripped into the front of the reactor buildings, uprooting everything its path and sweeping them away on a tide of filthy seawater. "The next I heard was that there was a problem with the electricity supply, and there were reports of debris floating in the sea," Yoshizawa says.

But the reality was even more menacing. The tsunami had crippled the plant's backup power supply, plunging it into darkness. Worse still, it had deprived four of the six reactors of the power required to cool the nuclear fuel rods inside.

If Yoshizawa could consider himself fortunate in those circumstances, it was that the two reactors under his control – units five and six – were already in cold shutdown for planned maintenance checks. But for as long as the power stayed off, nuclear fuel rods in the remaining four reactors would melt, causing a potentially catastrophic release of radioactive material that would reach far beyond Fukushima.

with IAEA
Atsufumi Yoshizawa meets a member of an International Atomic Energy Agency delegation at the Fukushima plant in May 2011. Photograph: Tepco


The prime minister at the time, Naoto Kan, has since claimed Tepco was poised to pull out all of its employees, believing the situation had become irrevocable. Kan, who has converted to the anti-nuclear cause since leaving office in autumn 2011, told staff a withdrawal would spell the end of Tepco. In his darkest moments, he would later admit, he was making mental preparations for a possible evacuation of greater Tokyo, an area of 35 million people.

Disagreements over a possible withdrawal rumoured to have taken place in the capital never filtered through to the men on the frontline, according to Yoshizawa. Some among the vast network of Tepco contractors and subcontractors ordered their employees to leave the plant. They were joined by other workers who lived in the communities in the path of the tsunami or which were imperilled by the reactor meltdowns. None of the workers had been able to communicate with their families; some would return to find their homes had been swept away. But at no point was anyone forced to stay, Yoshizawa said.

"I never thought of leaving. I had to stay and get a grip on the situation. I wasn't thinking about my family, only about the other workers and how worried they must have been about their own families.

"We knew that we would not be replaced. No one was forced to stay, but those of us who remained knew that we would be there until the end. We knew that we were the only people capable of saving the plant. Our determination surpassed all other considerations."

Yoshizawa says the hardest part of his job was sending junior colleagues into dangerous situations. The plant was frequently rocked by strong aftershocks, and the proximity of so much water to electrical equipment was an ever-present danger, as was the risk of acute radiation sickness.

The day after the tsunami, the plant was rocked again when a hydrogen explosion ripped though the building housing reactor No 2. Within days, two more units would suffer similar explosions.

"Several workers were injured during the hydrogen explosions, and telling people to go back into dangerous areas was tough. But [Masao] Yoshida [the then plant manager] never asked anyone to do the impossible; he knew that would only put lives at risk. By taking that approach, he united us all behind our mission."

Aerial shot of the No 3 nuclear reactor at the Fukushima Daiichi nuclear plant in Minamisoma. Photograph: Reuters/Digital Globe


Momentary relief came when Yoshizawa was moved to a disaster-response headquarters 5km from the plant. While he was there, the Fukushima crisis entered an even more dangerous phase, as two explosions in reactor buildings hampered efforts to direct a constant stream of coolant water at overheating fuel rods.

After three days off-site, Yoshizawa and several Tepco colleagues decided they had no choice but to return to Fukushima Daiichi. As they left the crisis headquarters, firefighters, police officers, soldiers and nuclear officials lined up to salute them. "We felt like members of the Tokkotai [the kamikaze pilots of the second world war] in that we were prepared to sacrifice everything," he says. "The people lined up outside never said as much, but I could tell by their expressions that they didn't think we would return."

By the time Yoshizawa arrived back at the plant, the international media were referring to him and his colleagues as the Fukushima 50, though the actual number of workers probably ran into the hundreds, with each team working shifts shortened by their exposure to constantly spiking atmospheric radiation. "I had heard the term Fukushima 50, but in fact there were many more people at the site, many more than I had imagined. And no one was panicking."

Over the weeks that followed, the Fukushima 50 resigned themselves to a daily routine of long shifts, wrapped head to toe in protective clothing, and uncomfortable nights sleeping on the floor of a radiation-proof building.

The scale of the disaster left the plant workers short of vital equipment. At one point there were not enough protective suits to go round, and stocks of personal radiation monitors had been damaged in the tsunami. "In normal circumstances you order what you need from outside, but we were in the middle of a nuclear evacuation, Japan was the scene of a major disaster, so no one could come near the plant," Yoshizawa says. "The few supplies we did have, we got ourselves."

Initially, the men survived on a diet of biscuits and other dried food. Deliveries of emergency supplies were out of the question while soldiers were still pulling bodies from the tsunami debris and getting aid to hundreds of thousands of survivors. The water shortage meant the Fukushima 50 were denied even bowls of warming instant noodles.

spray green
Tepco workers spray a green, resin-based dust protectant on the ground in the common pool area of the damaged Fukushima Daiichi plant. Photograph: Tepco/EPA


For the first fortnight of the crisis, each worker was given just one 500-millilitre PET bottle of water that had to last two days. "It was two weeks before I had my first cup of coffee," Yoshizawa says. "It tasted fantastic."

The long working hours, combined with a poor diet and sleep deprivation, took their toll on his health. He lost a lot of weight and his blood pressure soared.

It wasn't until December 2011, when the government declared the damaged reactors had reached a stable state known as cold shutdown that he and his colleagues could return to anything resembling regular working conditions.

Almost two years after the tsunami, the men who stayed behind at Fukushima Daiichi and spared Japan from an even worse fate occupy an uncomfortable place in the country's post-disaster psyche. While the Chilean miners who spent 69 days trapped deep underground in 2010 were feted as national heroes, most of the Fukushima workers continue to live unseen in the shadow of the disaster.

Tepco turns down most interview requests, and all but two of the handful of workers who have commented publicly did so on condition of anonymity. Most have chosen to remain silent, fearing they would be ostracised in the communities they tried, but failed, to prevent from turning into post-nuclear wastelands for years, perhaps decades.

Yoshizawa understands their anger. "Generally speaking, people in Japan believe we were the cause of the accident, and it's important to bear that in mind. As Tepco employees we have to take responsibility for the accident, and ensure that it never happens again. It's a matter of regaining people's trust, but it will take time.

"Looking back, maybe there were things we could have done better to prepare, but at the time we did everything possible to respond to the accident."

The perception that the workers perpetrated the accident and then botched their response appeared to permeate every level of Japanese society. The Fukushima 50 waited 18 months before the then prime minister, Yoshihiko Noda, publicly thanked them for "saving Japan", a gesture repeated this month by his successor, Shinzo Abe.

Another explosion rocks the Fukushima nuclear plant in Japan Photograph: ABC TV/EPA


If official expressions of gratitude were a long time coming, the men were buoyed from messages of support from all over the world, some of which decorate a huge Japanese flag that hangs in the Fukushima Daiichi central control room. Yoshizawa said Noda's visit to the plant last October was an honour, but added: "I don't consider myself a hero, but when I hear people thanking us for what we did, I'm grateful."

His account of a temporary return to "civilian" life one month after the disaster is perhaps the most telling commentary on the Fukushima 50's unheralded heroism.

As Yoshizawa left the plant, along with several other workers, to spend a few days with his family, he stripped to his underpants, completed a compulsory radiation check and changed into a tracksuit that was at least a size too big. He had grown an impressive beard, and his hair had become greasy and matted after four weeks without a bath or shower.

A few hours later, their bus arrived at Tokyo Station, where they were left to catch trains to their respective homes. "We must have looked strange, stepping off that bus in ill-fitting tracksuits, with long beards and dishevelled hair, and each carrying a plastic bag containing a few possessions," he says.

"But as we walked into the station no one gave us a second glance. Life in Tokyo appeared to be carrying on as normal, as if the Fukushima disaster had never happened. I sat down on the train and immediately noticed that people were avoiding sitting next to me."

radiation test
A child undergoes a radiation test in Nihommatsu, Fukushima prefecture. Photograph: Newscom/Kyodo/Wenn.com


Yoshizawa declined to divulge his internal radiation levels. They are abnormal, he admits, but not so high that he can never work at a nuclear power plant again. "I am not worried about my health." He has, by choice, had just one counselling session since he left Fukushima Daiichi. "Others have done it more regularly, it's important to have someone to talk to freely. But I don't kid myself that life will ever be the same. As a Tepco employee, returning to a normal life is impossible."

While they slowly withdraw from Japan's public consciousness, the ranks of the Fukushima 50 say they will never forget their time at the centre of a nuclear disaster that, without them, could have been far worse.

"There is a special bond between us," Yoshizawa says. "I can't put it into words – it's just a feeling we have towards one another. I guess it's the same as the camaraderie soldiers experience in wartime. In our case, the enemy was a nuclear power plant. And we fought it together."














”They put themselves under one kind of self anesthesia. As if there were no nuclear power plant accident, no radio activities. ”

















01 /19 2013













さんきゅー! エリー


01 /17 2013

Historic Move: IAEA Shifts 47 Japanese Reactors Into “Long-Term Shutdown” Category

Wednesday 16 January 2013

long term shutdown

In an unprecedented move, the International Atomic Energy Agency (IAEA) has shifted 47 Japanese nuclear reactors from the category “In Operation” to the category “Long-term Shutdown” (LTS) in its web-based Power Reactor Information System (PRIS). The number of nuclear reactors listed as “In Operation” in the world thus drops from 437 yesterday to 390 today, a level last seen in Chernobyl-year 1986 and a dramatic step of the IAEA’s official statistics in recognizing industrial reality in Japan. This is without doubt a unique revision of world operational nuclear data.


However, numerous questions remain. The definitions of the IAEA’s reactor status categories remain unclear. Units can remain in the LTS category for many years, without any apparent limit. Japan has now 48 units listed as LTS, one of which is the fast breeder reactor Monju that has not been generating electricity since a sodium fire severely damaged the plant in 1995, while three further units at Kashiwazaki-kariwa have not been generating power since an earthquake hit the site in 2007.

Japan Nuclear share

Of the other 47 Japanese units, 42 have been retroactively classified as LTS as of 1 January 2012 (strangely including the 3 Kashiwazaki-kariwa units), while five reactors have retroactively entered that listing between 14 January and 26 March 2012. One reactor, Tomari-3 in Hokkaido—the last one to generate electricity before the country entered a two-month nuclear-free period between 5 May and 5 July 2012—remains, for unknown reasons, in the categories “In Operation” (world overview) and “Operational” (country file). This is despite the fact that only two reactors are currently effectively generating power in Japan, units 3 and 4 at the Ohi plant in Fukui Prefecture.



The future of the Japanese nuclear power plants remains highly uncertain. In spite of a clearly more pro-nuclear government that came in with the election of Prime Minister Shinzo Abe, it will likely take years until more power plants could get back on line. Abe stated on 4 January 2013:

"We will first of all determine whether or not to restart nuclear power plants on the basis of scientific safety standards. Then over the course of roughly three years we will assess the futures of existing nuclear power plants and transition to a new stable energy mix over ten years. The new construction or replacement of nuclear power plants is not a matter that is able to be determined immediately. Naturally this is an area in which we should make our determination in accordance with the principle of gradually decreasing our degree of reliance on nuclear power to the greatest extent possible."

world in operation

Other sources have also suggested that it could take a long time for nuclear plants to adapt after the newly established Nuclear Regulatory Authority will come up with new safety standards in July 2013.











Blue Dolphine

ボア君 23歳
ラビ君 21歳
エリー 11歳 去
(ラブラドール犬 ♀)
ステラ 1歳



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