Blog Archive

Wednesday, 2 September 2015

‘Political rhetoric, not science’: Greenpeace slams IAEA Fukushima report

Greenpeace has lashed out against the conclusions of IAEA’s latest report on the Fukushima disaster, calling the claim that radioactive exposure is “unlikely” to result in increased thyroid cancer risk in children a political rhetoric rather than science.
On Monday, IAEA said that despite uncertainties about the radiation doses incurred by children immediately after the accident, “an increase in childhood thyroid cancer attributable to the accident is unlikely.”

READ MORE: Child cancers ‘attributable’ to Fukushima disaster ‘unlikely’ to increase – IAEA

On Tuesday, Greenpeace slammed the conclusions of the UN body as being ‘political rhetoric’.
“Nobody knows how much radiation citizens were exposed to in the immediate days following the disaster. If you don’t know the doses, then you can’t conclude there won’t be any consequences. To say otherwise is political rhetoric, not science,” said Kendra Ulrich, senior global energy campaigner with Greenpeace Japan.
Part of the reason why no solid data is available regarding the potential exposure of the civilian population, as IAEA notes, resulted from the chaos and unpreparedness of the authorities to deal with and document the radiological impact of the March 2011 industrial disaster. Besides security and design “weaknesses” at the nuclear facility, IAEA also noted the government’s failure to swiftly and uniformly distribute stable iodine to block radiological effects in humans.

Greenpeace notes that those were evident failures on behalf of both Tepco and Tokyo, and remains certain that there is no safe level of radiation exposure following a nuclear disaster.
Meanwhile, Japanese media reported that yet another youth has been diagnosed with thyroid cancer, bringing the total number of young victims to 104, out of the 385,000 Fukushima Prefecture non-adult residents at the time of the accident.


At the same time, the prefectural government committee investigating the issue said that “as of now, it is unlikely for the thyroid cancers found in Fukushima Prefecture to have been caused by the nuclear power plant accident,” Asahi News quotes.
Greenpeace blames IAEA for being complicit in covering up the truth about the potential harm posed by Fukushima fallout.
“The IAEA report actively supports the Abe government’s and the global nuclear industry’s agenda to make it appear that things can return to normal after a nuclear disaster,” Ulrich said. She accused Tokyo of giving the green light for Fukushima residents to return home, despite the risk of further nuclear exposure.
The organization also criticized the government’s move to restart nuclear power plants in the country. Last month, the Japanese government approved the program, which would let evacuees temporarily return to their homes for up to three months. The program is a step towards lifting the evacuation order and encouraging people to go back to their former residencies.
“But there is nothing normal about the lifestyle and exposure rates that the victims are being asked to return to,” Ulrich continued. “To intentionally subject nuclear victims to raised radiation levels is unjustified, particularly when we have the tragic reminder of Chernobyl where we saw increased rates of cancers more than five years after the crisis.”
The environmental NGO claims that its July investigation registered radioactive contamination levels in Fukushima prefecture at such a “high level” that it would be “impossible” for people to return.
Tokyo plans to lift the evacuation order by spring 2017 for many parts of the evacuation area stretching to a 20-kilometer radius around the Fukushima plant in addition to other zones that had high levels of radiation. Currently about 79,000 people from 10 localities remain evacuated.
Source: RT

Tuesday, 1 September 2015

WTO delays panel decision on ROK

TOKYO (Jiji Press) — The World Trade Organization has put off a decision on whether to set up a dispute settlement panel on South Korea’s import ban on Japanese fishery products, the Fisheries Agency said Monday.

At a meeting Monday, the WTO stopped short of making a decision as South Korea did not agree to the establishment of the panel. But the WTO is expected to approve the setting up of the panel as requested by Japan at its next meeting, on Sept. 28.

South Korea introduced the ban on some fishery products from eight prefectures, including Fukushima, in the wake of the reactor meltdown at Tokyo Electric Power Co.’s Fukushima No. 1 nuclear power plant.

Source: Japan News

Miyagi residents physically block officials from surveying proposed nuke waste dump sites

SENDAI – Residents of three Miyagi Prefecture towns selected as candidate sites for hosting a permanent nuclear waste disposal facility barred the entry Monday of Environment Ministry officials seeking to carry out survey work.

People in the towns of Kami, Kurihara and Taiwa stalled the officials’ plan to conduct geological surveys needed to determine which of the three locations would be best to host the site, which will permanently store radioactive waste that spewed from the Fukushima No. 1 power plant following the March 11, 2011, Great East Japan Earthquake.

In the Tashirodake area of Kami on Monday morning, some 350 residents turned out in a light rain to protest the visit, holding banners and signs and yelling “Protect children’s future!” and “Get lost!”
They also physically blocked the officials’ access to the areas.

An Environment Ministry official meanwhile said the ministry will consider holding a town meeting in Kami in line with a request by the municipal government.

Plans to start ground surveys in the towns have been stalled since October, when the Environment Ministry began visiting them.

Miyagi Gov. Yoshihiro Murai criticized the residents’ demonstrations, saying they should wage their battle against the nuclear dump site in the courts.

“They should open the land for a government survey without hesitating,” Murai said. “If they disagree with the government plan, they should go to court.”

Post-3/11 nuclear waste is being temporarily stored on farms around the prefecture and farmers hosting the waste are demanding the government build a proper storage site.

Source: Japan Times

No disaster prevention scheme worked out for 17 nuclear facilities

No work has been done to establish a disaster prevention scheme for 17 nuclear facilities despite the fact the central government laid out its policy nearly three years ago to review the country's nuclear disaster prevention structure in the wake of the Fukushima nuclear meltdowns.

The 17 nuclear facilities consist of nuclear fuel processing and reprocessing and experimental and research facilities across the country that are subject to the Act on Special Measures Concerning Nuclear Emergency Preparedness. No discussion has been held on disaster prevention schemes for such facilities. Some of them are located in urban areas, but local governments hosting such facilities have been urging the central government to review the country's nuclear disaster prevention scheme as local governments are unable to reflect such a scheme in their disaster prevention plans including those for the evacuation of local residents.

The Power and Industrial Systems Research and Development Center, a nuclear research arm of Toshiba Corp., is one of the 17 facilities. Its premises are situated side by side with Nippon Steel & Sumikin Pipe Co.'s steel plant in Kawasaki where a fire broke out on Aug. 24. The nuclear facility is located about 300 meters from the fire site. Toshiba said, "It was not affected by the fire." It went on to say, "The research facility is a basic facility for development of nuclear technology and it is a reactor with a maximum output of 200 watts which is extremely low."

Haneda Airport is about 1 kilometer from the facility on the other side of the Tama River. But Toshiba said, "We assess that the assumed annual radiation dose in the event of a fire or an airplane crash is 1 millisievert (the maximum permissible level of annual radiation exposure for an ordinary person) or lower."

The Nuclear Regulation Authority (NRA) provisionally designated disaster prevention priority areas for the 17 facilities at zones within a radius of between 50 meters and 10 kilometers from the facilities, depending on their scale and type -- the same as those set before the Fukushima nuclear disaster. Meanwhile, the guidelines for countermeasures against nuclear disasters formulated in October 2012 under the Act on Special Measures Concerning Nuclear Emergency Preparedness expand the disaster prevention priority areas for nuclear power plants to about nine times as large as those set before the Fukushima disaster. But the guidelines say that the disaster prevention priority areas for the 17 nuclear facilities will be discussed with an eye toward reviewing them and be reflected in the guidelines. The guidelines also say that criteria for designating evacuation areas and methods are "issues to be discussed in the future."

According to the NRA's Secretariat, however, no specific discussion on such issues has been made. An official of the secretariat said, "The NRA has been taking time to sort things out because the facilities vary in type and size from one another."

The disaster prevention priority area for Toshiba's research facility is set at a radius of 100 meters which falls within its premises. But in 2013, the Kawasaki Municipal Government added "release of radioactive materials outside of the facility" to the list of assumed conditions set in its disaster prevention plan. But no decision has been made on specific areas and methods of evacuation. A municipal government official said, "Because the central government has not shown its criteria, we are watching the progress."

About 4,000 people live in a provisional disaster prevention priority area for a nuclear fuel processing facility in the Kanagawa Prefecture city of Yokosuka, but the Kanagawa Prefectural Government has not been able to revise its disaster prevention plan. The Kanagawa Prefectural Government has been requesting the central government in writing every year since 2012 to review the guidelines.

There are three nuclear facilities including a university research unit and a nuclear processing facility in Osaka Prefecture, and they are located close to residential areas. The governments of Osaka, Aomori, Ibaraki and Okayama prefectures have been urging the central government in writing and verbally to review the guidelines.

Hirotada Hirose, professor emeritus at Tokyo Woman's Christian University, said, "As long as the facilities are dealing with nuclear materials even though they are relatively small, a nuclear disaster could occur. The NRA should review the countermeasures that are ambiguous at present as soon as possible after properly assessing the risks."

Source: Mainichi

Ex-Fukushima No. 1 worker sues Tepco over cancer

SAPPORO – A former worker at the Fukushima No. 1 power plant has filed a damages suit against Tokyo Electric Power Co. and others, claiming that he developed cancer due to exposure to radiation after the March 2011 nuclear disaster.

His lawyers said Tuesday the suit, filed in the Sapporo District Court, is the first litigation on causal relations between cancer and work to deal with the crisis.

The 57-year-old man is seeking a total of ¥65 million in damages from Tepco, contractor Taisei Corp. and its subcontractor.

According to his complaint, cancer was detected in his bladder in June 2012, in his stomach in March 2013 and in his sigmoid colon in May 2013 after he worked as a heavy equipment operator at Fukushima No. 1 between July and October 2011.

In August 2013, the man filed for workers accident compensation with the Tomioka Labor Standard Inspection Office in Fukushima Prefecture.

After the application was rejected in January this year, he requested that the Fukushima Prefectural Labor Bureau review the decision.

Records show that the man received a total of 56.41 millisieverts during his work at the power plant, but he claims to have been subjected to more than 100 millisieverts and says he sometimes worked without a dosimeter.

The government uses the 100-millisievert threshold to consider whether cancer has a causal link with radioactive exposure.

Tepco said it will respond sincerely after examining the lawsuit.

Source: Japan Times

How nuclear-free Japan made it through hottest summer yet without brownouts

TOKYO — The nation’s nuclear power generators having been shut down since 2011. Summer temperatures, with their commensurate power demand, have been climbing. Yet warnings at the time of the nuclear plant shutdowns, to the effect that the aging thermal generators would not be able to meet peak demands, have not come to pass.

What’s made it possible to keep the juice flowing? J-Cast News (Aug 27) reports that one factor has been the growing use of solar power, which when demand is highest during daylight hours has been pitching in to keep the air conditioners chugging along.

During two straight weeks of sunny weather, and particularly from July 31 to August 7—during a record-breaking string of eight consecutive “moshobi,” during which daytime peak temperatures in Tokyo surpassed 35 degrees Celsius—the power suppliers came through with flying colors.

According to Tokyo Electric Power Co (TEPCO), a new record of 29.57 million kilowatts of power demand was set at 1 p.m. on August 7. Fortunately even without nuclear power, use of outside suppliers to supplement TEPCO’s power generated in-house meant that usage by its own thermal plants reached 92% of capacity, leaving it with a surplus of 8%.

From the beginning of August, a source within the power industry revealed that “as we’re getting lots of solar power from noontime, there’s no problem, even without the nuclear reactors. They’re supplying enough that we can even hold back on the thermal generator output.”

What’s so remarkable was that in addition to the 23.84 million kilowatts being produced by TEPCO’s own generators, 9.91 million kilowatts, or about 20% of the total, were supplied by outside companies, which TEPCO has contracted to buy at fixed prices. A good portion of these are sourced from solar or wind power.

As of the end of June this year, some 7.9 million kilowatts of solar and other forms of renewable energy are serving TEPCO’s network, which on sunny days are calculated to be capable of supplying the amount of power provided by the nuclear plants. About half of the 9.91 million kilowatts provided by the outside suppliers is said to be sourced from solar power.

The situation is similar in other regional power utilities. On Aug 4 at 4 p.m., the time of highest power demand in Kansai reached 25.57 million kilowatts. Of Kansai Electric Power Co’s 27.81 million kilowatts maximum capacity, 6.34 million kilowatts are supplied to KEPCO by outside firms, again about half of which is solar energy.

The day of highest demand for Kyushu Electric Power Co, Aug 6 at 4 p.m., was 15 million kilowatts. Its peak capability is 17.21 million kilowatts, of which 4.70 million are sourced from outside suppliers—nearly as much as the 5.17 million the island’s five nuclear generators used to produce.

The J-Cast News reporter reminds readers that once night falls, solar power generation naturally drops to zero, and that output also declines on cloudy days. But fortunately the kind of hot, sunny afternoons when power demand is at its highest, coincide with the time when solar power generation is at its most efficient. What’s more, buying power from these suppliers lowers the burden on the power utilities’ thermal reactors and helps reduce energy consumption, so it’s not a bad thing at all.

That said, solar is not a perfect solution, since demand for air conditioning on some days does not taper off quickly with the coming of darkness. Still, its contribution to the power grid during this past month has turned out to be an unexpected and pleasant surprise.

Source: Japan Today

"New case of thyroid cancer diagnosed in Fukushima; brings number to 104

FUKUSHIMA--An investigation into health problems triggered by the 2011 nuclear disaster here turned up a new case of thyroid cancer in a young person who lived near the stricken plant.

The latest diagnosis brings to 104 the number of people out of the 385,000 or so Fukushima Prefecture residents who were 18 years old or younger at the time of the accident that are confirmed to have thyroid cancer, prefectural authorities said Aug. 31.

However, the prefectural government committee investigating the issue of health problems said that "as of now, it is unlikely for the thyroid cancers found in Fukushima Prefecture to have been caused by the nuclear power plant accident."

The latest check was conducted between April and the end of June.

Source: Asahi Shimbun

Fukushima Report Dangerously Downplays Ongoing Health Risks: Greenpeace

"The IAEA report actively supports the Abe government’s and the global nuclear industry’s agenda to make it appear that things can return to normal after a nuclear disaster."



A new report from the International Atomic Energy Agency (IAEA) "downplays" the continuing environmental and health effects of the Fukushima nuclear meltdown while supporting the Japanese government's agenda to normalize the ongoing disaster, Greenpeace Japan charged on Tuesday.

The Vienna-based IAEA released its final report Monday on the 2011 triple meltdown at the Fukushima No. 1 nuclear power plant. While the agency pointed to numerous failings, including unclear responsibilities among regulators, weaknesses in plant design and in disaster-preparedness, and a "widespread assumption" of safety, it was more circumspect with regard to health concerns.

The Fukushima disaster released vast amounts of radiation, leading to fears that cases of thyroid cancer in children would soar as they did following the Chernobyl disaster of 1986.

The 200-page report sought to assuage those worries, stating: "Because the reported thyroid doses attributable to the accident were generally low, an increase in childhood thyroid cancer attributable to the accident is unlikely."

That assertion wasn't bulletproof, however. The report added: "[U]ncertainties remained concerning the thyroid equivalent doses incurred by children immediately after the accident."

In a press statement, Greenpeace Japan seized on the information gap.
"The IAEA concludes that no discernible health consequences are expected as a result of the Fukushima disaster, but admits important uncertainties in both radiation dose and long-term effects," said Kendra Ulrich, senior global energy campaigner with Greenpeace Japan. "Nobody knows how much radiation citizens were exposed to in the immediate days following the disaster. If you don’t know the doses, then you can’t conclude there won’t be any consequences. To say otherwise is political rhetoric, not science."

The IAEA report conveniently comes as pro-nuclear Prime Minister Shinzo Abe systematically seeks to lift evacuation orders and re-start the country's nuclear program.

"The IAEA report actively supports the Abe government’s and the global nuclear industry’s agenda to make it appear that things can return to normal after a nuclear disaster," Ulrich said. "But there is nothing normal about the lifestyle and exposure rates that the victims are being asked to return to."

In July, Greenpeace Japan charged that the IAEA "has sought to downplay the radiological risks to the population since the early days in 2011. In fact, it produced two documents that can be said to have laid the foundation and justification for Abe’s current policy of de facto forced resettlement."
Exploring the political dynamics further, Ulrich wrote at the time:
Over four years after the triple reactor core meltdowns and exploded containment buildings at the Fukushima Daiichi nuclear power plant, the majority of the Japanese public has remained opposed to any nuclear restart. The country has been completely nuclear-free for nearly two years, thanks in large part to significant public opposition, in spite of the massive pressure from nuclear utilities and the Abe government on local city governments.
However, these utilities are massively powerful and the Abe government is wholly in bed with them.
In an effort to reduce public opposition, Abe has been pushing forward the pro-nuclear agenda to 'normalize' a nuclear disaster. If the public can be convinced that less than five years after the worst nuclear disaster in a generation, citizens can go home and return to life the way it was before the disaster – with no additional health risks – then that is a powerful argument against the majority of Japanese citizens who oppose  nuclear reactor restarts.
Japan's Asahi Shimbun newspaper reported Tuesday that evacuees from three Fukushima Prefecture localities who were displaced by the nuclear disaster started temporarily returning to their homes on Monday to prepare for their eventual permanent return.
"But applicants for the temporary stay program that began that day totaled 1,265, less than 10 percent of about 14,000 eligible as of Aug. 30," the paper reported. "The small number indicates that an overwhelming majority of evacuees are still concerned about radiation levels and prospects for a return to normalcy in their hometowns."

Source: Common Dreams

IAEA's final report on Fukushima disaster slams safety myth, downplays thyroid cancer fears

The IAEA released its final report Aug. 31 on the triple meltdown at the Fukushima No. 1 nuclear power plant that spewed out vast amounts of radiation, leading to fears that cases of thyroid cancer in children would soar.

However, the report downplayed those fears, stating: “Because the reported thyroid doses attributable to the accident were generally low, an increase in childhood thyroid cancer attributable to the accident is unlikely.”

The 200-page report, compiled by 180 experts from 42 IAEA member countries, was released along with five technical volumes totaling 1,000 pages, and is to be presented at the IAEA’s general meeting scheduled to start on Sept. 14.

The materials are available on the IAEA’s official website at (

“A major factor that contributed to the accident was the widespread assumption in Japan that its nuclear power plants were so safe,” the IAEA stated, adding that facilities and emergency procedures to address a major accident, such as the one triggered by the Great East Japan Earthquake and tsunami, were woefully insufficient.

The report begins with the foreword by Yukiya Amano, director-general of the IAEA.
“There can be no grounds for complacency about nuclear safety in any country,” Amano wrote.

With regard to other causes of the Fukushima disaster, the report cited flaws in the design of nuclear facilities and emergency procedures. It also criticized the plant operator, Tokyo Electric Power Co., for not having taken appropriate preparations in case outside power sources were lost for a prolonged period or anticipated accidents simultaneously occurring at multiple reactors.

The IAEA report pointed out that TEPCO did not take steps against towering tsunami inundating the plant even though it had anticipated that possibility based on a pre-disaster assessment by the government.

The final report also mentioned the effects of radioactive iodine released from the plant on the thyroid glands of children living near the nuclear facility.
But it also noted that uncertainties still linger about radiation doses children incurred immediately after the accident.

Source: Asahi Shimbun

IAEA releases final biased report on Fukushima accident


The International Atomic Energy Agency says a major factor behind the 2011 Fukushima nuclear accident was a widespread assumption in Japan that nuclear power plants were safe.

The IAEA released a final report on Monday on the meltdown at the Fukushima Daiichi nuclear power station. About 180 experts from more than 40 IAEA member countries contributed to the 1,200-page-plus report.

The report says that Japan was not sufficiently prepared for a severe nuclear accident due to the assumption that nuclear plants were safe. It says the Fukushima Daiichi plant had weaknesses in design and emergency preparedness.

The March 2011 accident came after a major earthquake and tsunami struck Fukushima Prefecture and the surrounding areas of northeastern Japan.

The report says the accident demonstrated the need to consider the potential for a combination of natural hazards to occur simultaneously. It says safety standards should also be continuously re-evaluated to consider advances in knowledge.

The report says no early radiation-induced health effects were observed among workers or members of the public.

It adds that although it can take decades for latent health effects to emerge, no discernible increase in such conditions is expected, given the low levels of radiation exposure among the general public.

The report also says thyroid abnormalities found in some children are unlikely to be associated with the nuclear accident, due to low exposure levels.

IAEA Director General Yukiya Amano says some of the factors that resulted in the Fukushima accident were not unique to Japan.

Amano says continuous questioning and openness to learning from experience are key to safety and are essential for everyone working in the industry.

The IAEA plans to submit the report to its General Conference this month to share the lessons on a wide scale and help improve the safety of nuclear plants.

"IAEA's final report on Fukushima disaster slams safety myth, downplays thyroid cancer fears"
The International Atomic Energy Agency says a primary factor behind the 2011 Fukushima nuclear disaster was a mistaken “assumption” among plant operators about the safety of reactors.
Source: NHK

Fukushima evacuees prepare for eventual return, but most are choosing not to

Evacuees from three Fukushima Prefecture localities who were displaced by the nuclear disaster started temporarily returning to their homes on Aug. 31 to prepare for their eventual permanent return.
But applicants for the temporary stay program that began that day totaled 1,265, less than 10 percent of about 14,000 eligible as of Aug. 30.
The small number indicates that an overwhelming majority of evacuees are still concerned about radiation levels and prospects for a return to normalcy in their hometowns.
Fukushima Governor Masao Uchibori said a secure environment must be in place for evacuees to participate in the preparatory program.
“What is most important is to provide a sense of safety and security,” he said at a news conference on Aug. 31. “Evacuees will not readily join the program unless they have easy access to health care, education and shopping areas.”
Residents of parts of Minami-Soma, Kawamata and Katsurao were ordered by the central government to evacuate when a triple meltdown occurred at the Fukushima No. 1 nuclear power plant as a result of the 2011 Great East Japan Earthquake and tsunami.
Last month, the government approved the program that would let evacuees from the three areas temporarily return to their homes for up to three months. The program is a step toward lifting the evacuation order and encouraging people to return home, as many have chosen to settle elsewhere after the prolonged evacuation.
In the village of Katsurao on Aug. 31, evacuee Kazuhiro Matsumoto, 59, was busy repairing the damaged walls of his home.
“It is nice to be back home, but I will miss my grandchildren after my return here,” Matsumoto said. “I am fixing my home because we need a place where my family and relatives can get together on New Year’s Day.”
While living in makeshift housing, Matsumoto has been working in cleanup operations in Katsurao for which his company was commissioned.
His son’s family of six already built a home outside the village and decided not to return to Katsurao to live.
Rice paddies across from Matsumoto’s home are overrun with weeds, with a large number of bags containing radioactive soil and other waste produced in decontamination operations piling up.
“Even though the authorities say we are safe, I am still anxious because we cannot see radiation,” he said.
The government plans to lift the evacuation order by spring 2017 for many parts of the evacuation area, which encompasses a 20-kilometer radius around the Fukushima plant and localities outside the zone that had high levels of radiation.
Officials from Minami-Soma, Kawamata and Katsurao hope to see the evacuation order lifted by next spring.
They have begun a preparatory program based on prospects that cleanup work will progress further in the coming months.
Local authorities say many general contractors will not accept assignments in the evacuation area. But they believe that work to mend local infrastructure and homes will proceed once evacuees are allowed to return home to live.
The number of residents who signed up for the preparatory program was low because many of the evacuees, primarily young couples, have decided to make a fresh start. They have purchased homes close to their workplaces or their children’s schools.
Four years after the onset of the nuclear disaster, about 79,000 people from 10 localities remain evacuated.
Source: Asahi Shimbun


Fukushima evacuees begin three-month stays in their homes ahead of final return

FUKUSHIMA – Evacuees from three municipalities in Fukushima Prefecture are being allowed to return home for long-term stays before the central government formally lifts the evacuation order for those areas.
The government says it made the move, which took effect Monday, because radiation levels have dropped sufficiently in Minamisoma, Kawamata and Katsurao since the March 2011 meltdowns at the Fukushima No. 1 nuclear plant.
The government will decide by November whether to lift the evacuation order after hearing from the evacuees.
The long-term stays are allowed for 14,255 people in 4,647 households, the largest number in the long-stay program so far.
Some areas will remain no-go zones because radiation levels remain high.
As of Monday, 1,308 people in 478 households, some 10 percent of the total, had reported to the government that they would start the long-term stays in their homes.
Decontamination work in residential areas in Kawamata and Katsurao was completed in summer last year, halving the average radiation level in the air to 0.5 microsievert per hour.
In Minamisoma, only 26 percent of decontamination work had been finished by the end of July, but natural falls in radiation levels were taken into consideration.
Dosimeters will be given to each household, while consultants will be dispatched to check the health status of residents. Minamisoma has set next April as its target date for the lifting of the evacuation order, while Katsurao and Kawamata are being less exact and have set the target for next spring.
Long-term stays have already been conducted in Tamura and part of Kawauchi, where evacuation orders have been removed, and in Naraha, where it is slated to be lifted on Wednesday.
Source: Japan Times

Cs-134/137 density became the highest reading at 4 points inside and outside Fukushima plant port

According to Tepco, Cesium-134/137 density reached the highest reading in 3 locations of Fukushima plant port.

The samples were taken on 8/28/2015. Those sampling locations are the center of Fukushima plant port, water intake of Reactor 1 and 2, where are outside of underground wall.

In the center of Fukushima plant port, Cs-134/137 density (79,000 Bq/m3 in Cs-134/137) became as double as the previous highest reading measured at this point this July.

Additionally, Cs-137 was detected for the first time in the North of the plant, where is outside of the port. The density was 800 Bq/m3.
Source: Fukushima Daiichi

Fukushima Staff to Start Pumping Radioactive Ground Water Away From Plant

Staff at the Japanese Fukushima Daiichi nuclear power plant will begin pumping groundwater from the plant's territory to prevent the buildup of radioactive liquid this week, the NHK television reported Monday.


MOSCOW (Sputnik) — Pumping will begin on September 3 and will be conducted through wells dug specifically for this purpose, the NHK reported.

According to experts of the TEPCO energy company, these measures will reduce the rate of accumulation of radioactive water in the ground under the plant, from where the dangerous fluid flows into the sea.

Currently, the volume of groundwater under the power plant is increasing daily by 300 tons. It is expected that after the start of pumping, the figure will be reduced to 150 tons per day, the media outlet reported.

TEPCO plans to clean the collected water from radioactive substances and drain it into the sea, according to the channel.

The company received permission to do so after long negotiations with the Fukushima Prefecture authorities and local fishing cooperatives. The agreement between the parties implies that the levels of radioactive substances in the water drained into the sea would not exceed the norm.

The Fukushima nuclear power plant was severely damaged in March 2011 after being hit by a 46-foot tsunami triggered by a massive offshore earthquake. Three of its six reactors went into meltdown, resulting in the release of radiation into the atmosphere, soil and sea.

Source: Sputnik News

2,000 people join nuclear disaster drill in Fukushima

MINAMISOMA, Fukushima -- The Fukushima Prefectural Government organized a nuclear disaster drill here on Aug. 30 ahead of nationwide Disaster Prevention Day on Sept. 1.

Some 2,000 people, including local residents, fire department officials, police officers and Self-Defense Force personnel, joined the general disaster drill in the city where some of its areas remain as evacuation zones following the 2011 nuclear meltdown.

The drill was held on the assumption that the Fukushima No. 1 Nuclear Power Plant, battered in the 2011 earthquake and tsunami, was hit by another massive tsunami triggered by a large earthquake.

The exercise supposed that the cooling system of the spent fuel pool at the Fukushima plant had stopped while undergoing decommission work, releasing radioactive material into the atmosphere.

Residents evacuated to a designated site and then went through a radiation exposure screening conducted by medical experts dressed in protective gear.

Source: Mainichi

Sunday, 30 August 2015

"Contaminated rainwater at Fukushima plant repeatedly leaked into sea

FUKUSHIMA -- Rainwater containing radioactive contaminants flowed from a drainage ditch by the reactor buildings at the Fukushima No. 1 Nuclear Power Plant into the sea on five occasions in just over four months, it has been learned.

The ditch is 2 meters deep and 2 meters wide, and stretches for about 800 meters. It was created to ferry rainwater from the plant grounds into the ocean, but in February this year it was learned that highly contaminated rainwater from the top of the No. 2 reactor building had flowed into the ditch and subsequently into the ocean. Tokyo Electric Power Co. (TEPCO), the operator of the plant, set up a 70-centimeter-high dam in the ditch, as well as eight pumps to move water from the ditch to another ditch that runs into a sealed harbor area. The pumps, which together can process rainfall of 14 millimeters per hour, were started on April 17 this year.

On April 21, however, loss of power caused by trouble with power generators resulted in all of the pumps shutting down, and contaminated water leaked into the sea. On July 16, rainfall rose to 21 millimeters per hour at one point. This was more than the pumps could handle, and workers confirmed that water flowed into the ocean. In all, five leaks from the ditch occurred in the period between April 17 and Aug. 27.

The concentrations of radioactive cesium and other radioactive materials in the contaminated rainwater ranged from around 20 to 670 times the safety level set for a "subdrain" plan in which decontaminated groundwater is to be released into the ocean.

The volume of leaked rainwater is unknown, but no changes have been seen in radioactive concentrations in the sea near the plant.

The Fukushima Prefectural Government on Aug. 27 issued a new request to TEPCO to introduce leak prevention measures. The next day, TEPCO raised the ditch dam by 15 centimeters, but Naohiro Masuda, chief decommissioning officer at Fukushima Daiichi Decontamination and Decommissioning Engineering Co., says, "Our main countermeasure will be to replace the ditch with a new one."

This new ditch is designed to carry rainwater into the sealed harbor area. Masuda indicated that until completion of the new ditch -- scheduled within the fiscal year -- additional leaks may be unavoidable. The plant therefore looks set to enter the typhoon season without full preparations against further leaks.

In February, after the rainwater leaks were discovered, fishermen protested that TEPCO had not released radiation measurements for the drainage ditch water for around 10 months. Negotiations with fishermen over the subdrain plan were subsequently put on hold. However, the Fukushima Prefectural Federation of Fisheries Co-operative Associations officially agreed to the plan after receiving notification from TEPCO and the national government regarding measures to prevent a recurrence of the leaks.

Regarding the rainwater leaks, federation chairman Tetsu Nozaki commented, "All we can do is to ask TEPCO to improve the situation. The subdrain plan is a separate issue, and there is no change in our acceptance of it."

Source: Mainichi

Tochigi town residents rally against selection as candidate site for final disposal of radiation-tainted waste

UTSUNOMIYA – About 2,700 residents of Shioya, Tochigi Prefecture, gathered Saturday to oppose the central government’s choice of the town as a candidate site for the final disposal of some of the radiation-tainted waste resulting from the 2011 Fukushima nuclear disaster.
The residents adopted a resolution urging the plan be scrapped. Among those taking part was Mayor Hirobumi Inomata from Kami, another candidate site in Miyagi Prefecture.
In Tochigi Prefecture, designated waste that contains more than 8,000 becquerels of radioactive cesium per kilogram is currently stored at about 170 different locations on a temporary basis.
For final disposal, the Environment Ministry selected state-owned land in Shioya at the end of July, but the plan has since met strong local opposition.
In 2012, another city in Tochigi Prefecture, Yaita, which borders Shioya, was selected as a candidate site for final waste disposal. However, the government was later forced to reconsider the decision due to fierce local opposition.
The state is planing to build landfill facilities for final disposal in five prefectures — Tochigi, Miyagi, Chiba, Gunma and Ibaraki prefectures — which lack the capacity to dispose of such waste at existing facilities.
In a related move Friday, three nuclear plant makers denied responsibility for the March 2011 Fukushima meltdown at the first hearing on a lawsuit seeking damages from the companies.
Representatives from Toshiba Corp., Hitachi Ltd. and General Electric Co. sought to dismiss the damage claims in Tokyo District Court.
The claims were lodged by about 1,400 people in Japan, including Fukushima residents, and 2,400 people from other places with nuclear plants, such as South Korea and Taiwan.
According to the plaintiffs, the plant makers insisted they have no obligation to compensate for damage from the accident at Tokyo Electric Power Co.’s Fukushima No. 1 nuclear plant, referring to the law on nuclear damage compensation, which stipulates that only power suppliers have responsibilities for nuclear accidents.
The plaintiffs claim that the law, which gives nuclear plant makers immunity from compensation claims, violates the Constitution and therefore is invalid. Under the product liability law and other laws, they are demanding payment of ¥100 each.
Meeting with the press after speaking in court, Kazue Morizono, a 53-year-old resident of Koriyama, Fukushima Prefecture, said she hopes the lawsuit will clarify responsibility for the nuclear accident.
Source: Japan Times

Morphological defects found in Japanese fir trees around Fukushima nuclear plant

Radiation spewed out by the crippled Fukushima No. 1 nuclear power plant may be responsible for differences in the growth of native Japanese fir trees in the area.
Researchers primarily from the National Institute of Radiological Sciences said Aug. 28 that many fir trees near the plant, as well as other areas, had undergone “morphological defects.”
They intentionally avoided words like abnormality, but used morphological defects and change.
Their studies showed that the changes occurred more frequently in areas with higher air rates of radiation.
"But it is still unclear whether the phenomenon has been caused by radial rays,” a team member concluded, adding that exposure to higher levels of radiation is “one possible cause.”
Conducted in January, the survey covered the town of Okuma in Fukushima Prefecture, located 3.5 kilometers from the plant, where radiation levels of 33.9 microsieverts per hour were detected, and two locations in the town of Namie, also in the prefecture.
While one of the Namie investigation sites is 8.5 km from the plant and measured 19.6 microsieverts per hour, readings of 6.85 microsieverts were detected at the other spot, located 15 km from the facility.
All the sites are within the government-designated difficult-to-return zone, meaning that the residents were evacuated and are prohibited from living there.
The team also examined firs in distant Kita-Ibaraki, Ibaraki Prefecture, which had radiation levels of 0.13 microsieverts per hour, for comparison.
In each of the four sites, the scientists checked 100 to 200 fir trees.
They found that more than 90 percent of firs in the Okuma site were not growing normally. Fir tree boles normally extend upward with two or so branches arising from them horizontally each year. But this was not the case.
Similar changes in shape were found in more than 40 percent of firs and around 30 percent of the trees, respectively, in the two Namie locations. Less than 10 percent of fir trees in the Kita-Ibaraki survey site also were different.
According to the NIRS, findings of studies concerning the 1986 Chernobyl nuclear disaster and other research revealed that conifers, such as firs and pine trees, are vulnerable to the effects of radiation.
However, the scientists noted that the problems reported in their latest survey may have been caused by animals, tree sickness or cold weather, not by exposure to strong radiation.
The Environment Ministry has been examining the impact of radial rays on local ecosystems since the nuclear crisis unfolded at the Fukushima nuclear plant four years ago. The NIRS study is part of those ministry efforts.
The governmental agency has to date monitored 44 kinds of animals and plants in areas around the damaged facility, but no other significant changes or abnormalities have been reported.
Tomoko Nakanishi, a professor of radiation plant physiology at the University of Tokyo, said the latest findings are invaluable as researchers have difficulty doing surveys in the difficult-to-return zone due to high radiation readings.
“There had been so little data on such areas,” she said.
But Nakanishi also pointed out it will require further research to conclude the morphological changes have been caused by exposure to radial rays.
“Other factors may have affected fir trees,” Nakanishi said. “Researchers need to examine through lab experiments what will happen when firs are exposed to high levels of radiation.”
Source: Asahi Shimbun

Saturday, 29 August 2015

3 Thyroid Cancer Cases Diagnosed in Kitaibaraki City, Ibaraki Prefecture -- Immediately South of Fukushima Prefecture

Kitaibaraki City, Ibaraki Prefecture, is located in the northeastern part of the prefecture, immediately south of Iwaki City, Fukushima Prefecture, and about 70 km south and slightly west of the Fukushima Daiichi nuclear power plant.

On August 25, 2015, Kitaibaraki City released the results of the thyroid ultrasound examination. Below is the English translation of the results and the related newspaper article.

 August 25, 2015
Division of Cooperative Community Development
Office of Health Support

【Regarding the Results of Thyroid Ultrasound Examination Project in Kitaibaraki City】

Kitaibaraki City implemented “Thyroid Ultrasound Examination Project: during the two-year period in Fiscal Year (FY) 2013-2014. (Project expenses: 37,173,000 yen)
Subjects were cityい residents age 0 to 18 at the time of the Fukushima Daiichi nuclear power plant accident. The examination was conducted in those age 0 to 4 in FY 2013 and other ages in FY 2014.
Regarding the examination results, the Kitaibaraki City Thyroid Ultrasound Examination Project Evaluation Council, consisting of experts and physicians, reported as follows:

  1. As screening examination, some would require a detailed examination or be diagnosed with cancer at a fix rate just as expected in a routine health check-up.
  2. The detailed examination result from FY 2014 revealed 3 cases of thyroid cancer.
  3. Radiation is unlikely to be the cause of these thyroid cancer cases.
FY 2013-2014 Thyroid Ultrasound Examination Results

 ※All participants or their guardians received explanations regarding radiation effects, purpose and method of the examination, and diagnostic category at orientation sessions ahead of time.
Those who were assessed to require a detailed examination (B & C diagnostic category) received explanation about the detailed examination during individual home visits.
Second-round screening is planned. The time of screening will be considered based on the opinions of physicians and experts.

Note: Diagnostic criteria employed by Kitaibaraki City are the same as in Fukushima Prefecture according to Oshidori Mako's inquiry with Kitaibaraki City Hall.

  • A1: no nodules or cysts found
  • A2: nodules ≦ 5.0 mm or cysts ≦ 20.0 mm
  • B: nodules ≧ 5.1 mm or cysts ≧ 20.1 mm
  • C: requiring immediate secondary examination
The Asahi Shimbun article dated August 26, 2015

Ibaraki Prefecture: Three Thyroid Cancer Cases in Kitaibaraki City from Last Fiscal Year Examination of Those Age 18 or Younger

Kitaibaraki City has been independently investigating the effect of radioactive substances  due to the Tokyo Electric Fukushima Daiichi nuclear power plant accident on children. On August 25, Kitaibaraki City released the results of the thyroid ultrasound examination conducted in FY 2014 on children age 18 or younger (note: at the time of the accident; at exposure). There were 3 cases of thyroid cancer, but it was judged unlikely to be due to the nuclear power plant accident.

After the nuclear power plant accident, the central government conducted thyroid examination in Fukushima Prefecture, but not in adjacent Kitaibaraki City. Due to requests from parents, the city conducted the examination independently. 1184 children who were age 4 or younger at the time of the accident underwent the examination in FY 2013, and none were diagnosed with thyroid cancer.

Examination subjects in FY 2014 was a total of 6,151 children 18 or younger (including children age 4 or younger who did not undergo the examination in FY 2013). Of these, 3,953 wanted to be examined. The results showed 1,746 with no findings, 1,773 to be followed with observation, 72 to require detailed examinations, and 2 to require detailed examinations immediately. 3 were diagnosed with thyroid cancer by the Thyroid Ultrasound Examination Project Assessment Council. However, the cancer was determined unlikely to be due to radiation exposure owing to the Fukushima nuclear power plant accident, considering the supposed exposure dose and the length of time since the accident. 

According to tweets by a freelance journalist Ryuichi Kino who contacted the Office of Health Support, Division of Cooperative Community Development, Department of Citizen Welfare at Kitaibaraki City Hall, 3 cancer cases were diagnosed from 74 (72 in category B and 2 in category C) who had detailed examinations, but apparently 2 cases who were in diagnostic category C were not automatically diagnosed with cancer. (It is unclear if this means the 2 "C" cases were eventually diagnosed with cancer after the detailed examination, or they were not diagnosed with cancer). All 3 have been operated on and apparently doing well. The city has no intention of releasing ages and sexes of the three patients, as such information might identify the individuals. Names of the Kitaibaraki City Thyroid Ultrasound Examination Project Evaluation Council members will not be released at the request of some of the members. The Council consists of 6 members — 1 thyroid specialist, 3 physicians including surgeon(s) and general practictioner(s), and 2 city officials. According to the Ibaraki Shimbun article, president of Kitaibaraki City Hospital, Dr. Yoshifumi Uekusa, stated, “Symptoms began to appear 5 years after the Chernobyl accident, and the exposure dose is less in Japan, so it is unlikely to be due to radiation effects.”  Apparently, Dr. Uekusa is a member of the Council. 

Oshidori Mako contacted Kitaibaraki City Hall and reported that the Thyroid Ultrasound Examination Project Assessment Council (which concluded, "Radiation is unlikely to be the cause of these thyroid cancer cases") included no experts in radiation protection or dose estimation. Oshidori Mako also noted that the radioactive plume blew in the south towards Iwaki City but the lack of precipitation prevented radionuclides from depositing on the ground as it did in Iitate Village. (This means the overall radioactivity of soil may not be high, but residents still might have been exposed to the radioactive plume when it passed through the area). The early exposure dose assessment, based on the soil deposition, has been inadequate for a place such as Iwaki City. 

As a matter of fact, paragraph C43 of UNSCEAR 2013 discusses the so-called "south trace" having much higher ratios of Te-129m and I-131 to Cs-137. This suggests a significant amount of radioactive iodine isotopes might have fallen in the "south trace" which includes Iwaki City. As Kitaibaraki City is immediately south of Iwaki City, and the air movement does not stop at the border between the two cities, it is possible for Kitaibaraki City to have received a similar amount of the radioactive plume as Iwaki City.

Source:  Fukushima Voice version 2

Morphological defects in native Japanese fir trees around the Fukushima Daiichi Nuclear Power Plant


After the accident at the Fukushima Daiichi Nuclear Power Plant (F1NPP) in March 2011, much attention has been paid to the biological consequences of the released radionuclides into the surrounding area. We investigated the morphological changes in Japanese fir, a Japanese endemic native conifer, at locations near the F1NPP. Japanese fir populations near the F1NPP showed a significantly increased number of morphological defects, involving deletions of leader shoots of the main axis, compared to a control population far from the F1NPP. The frequency of the defects corresponded to the radioactive contamination levels of the observation sites. A significant increase in deletions of the leader shoots became apparent in those that elongated after the spring of 2012, a year after the accident. These results suggest possibility that the contamination by radionuclides contributed to the morphological defects in Japanese fir trees in the area near the F1NPP.


During the Fukushima Daiichi Nuclear Power Plant (F1NPP) accident that occurred in March 2011, radionuclides that were released into the atmosphere contaminated the surrounding environment1,2. Since the accident, much attention has been paid to the biological consequences of contamination by radionuclides. To detect the biological changes in the environment, various wild organisms, such as Japanese monkeys3, lycaenid butterflies4, and gall-forming aphids5, inhabiting the surrounding area have been investigated as possible indicator organisms. However, further studies using radiation-responsive indicator organisms help us to reach a consistent conclusion, whether radiological contamination from the F1NPP accident had a biological impact on the environment.
For the purpose of biomonitoring of the radiological contamination, nevertheless, coniferous plants have been demonstrated to be suitable indicator organisms because of their high radiosensitivity, which was revealed decades ago by field examination using gamma irradiation facilities6,7,8,9. Radiosensitive damages in conifers were reported after the Chernobyl nuclear accident in 1986, where two local coniferous species, Scots pine (Pinus sylvestris) and Norway spruce (Picea abies), showed distinct biological damage in the radioactively contaminated areas10,11,12. Under experimental and accidental exposure, morphological changes, particularly in branching of the main axis, were shown to be the most frequently observed radiosensitive responses of coniferous plants6,7,8,9,10,11,12.
Coniferous tree species are grown in the area highly radioactive contaminated by the F1NPP accident, where Japanese fir (Abies firma) is one of the most common naturally grown species. Different from other coniferous species, young-tree populations of Japanese fir are abundant, because this species has the characteristic ability to sprout even on the shaded forest floor. The short height of young trees enables the easy observation of morphological changes in the whole tree. In addition, the regular annual branching of Japanese fir trees enables determination of the year that any morphological changes occurred through a number of past years (Fig. 1).

 In this study, we used the Japanese fir tree as an indicator organism to detect the environmental impact of radiological contamination caused by the F1NPP accident. We examined the morphological changes in annual leader shoots for the past five years within the highly contaminated area around the F1NPP13. The investigation was carried out in January 2015 at 3 observation sites (S1, S2, and S3), at different distances from the F1NPP and with different contamination levels (Fig. 2, Table 1). The three observation sites were situated in “Area 3” where it is expected that the residents have difficulties in returning for a long time (Ministry of Economy, Trade and Industry). Fir trees were also examined in a slightly contaminated control site (S4), southwest of the F1NPP.


Most of the naturally grown Japanese fir trees showed a typical monopodial branching pattern to form a trunk with one main axis (Fig. 3A), whereas some trees showed distinctive morphological defects on the main axis of the trunk (Fig. 3B,C). Independently of the growing site, these defects were characterized by irregular branching at the whorls of the main axis with a distinct deletion of the leader shoot that normally elongates vertically to form the main axis. The space of the deleted leader shoot was filled in by the remaining lateral branches that either extended upwards (Fig. 3B) or retained their horizontal position (Fig. 3C).

 The overall frequency of the morphological defects of the main axis varied among observation sites, S1, S2, and S3, but it was significantly higher in each site compared to the control, S4 (chi-square test with df = 1, p = 2.1 × 10−58, 3.7 × 10−17, and 8.1 × 10−7, respectively, Bonferroni-corrected; Fig. 4). The frequency corresponded to the ambient dose rate at the observation sites that represented the local levels of radionuclide contamination (S1 > S2 > S3 > S4, Table 1). A high frequency of defects was observed in S1, where 125 out of 128 trees showed branching defects of the main axis.

 Branching defects of the main axis were analyzed separately in each annual whorl (Fig. 5). Compared to the whorls of 2010, which had been generated before the F1NPP accident, the frequency of deleted leader shoots was significantly increased in the whorls after 2012 (sites S1 and S3), or those after 2013 (site S2). The frequency peaked in the whorls of 2013 and tended to decrease in the whorls of 2014 in every observation site. The variation patterns in the series of annual whorls were similar among the sites, whereas no annual variation was observed in the control site, S4. These results indicated that the deletion of leader shoots occurred most frequently in the whorls that elongated from terminal winter buds during the growing season of 2012–2013.

 Despite the significant increase in the frequency of deleted leader shoots in annual whorls around 2013 in the observation sites S1–S3, the number of lateral branches that elongated from the same whorls did not show annual variation that corresponded to the deletion frequency of leader shoots (Fig. 6). The number of lateral branches was not different among annual whorls even in S1 (one-way ANOVA, p = 0.84), in which the frequency of leader shoot deletions varied most intensely compared to the other observation sites (Fig. 5). On the other hand, the number of lateral branches showed significant annual variation in S2, S3, and S4 (one-way ANOVA, p = 1.4 × 10−7, 6.3 × 10−3 and 1.5 × 10−8 for S2, S3, and S4, respectively); however, the annual variation patterns were independent from the frequency of leader shoot deletions. In addition, the variation in lateral branch number among the sites did not correspond to the frequency variation of deleted leader shoots. This indicated that the deletion of leader shoots occurred independently of the change in lateral branch number that elongated from the whorls.

 Differences in the development of the leader shoots and lateral branches were also observed from a close inspection of the defected whorls. At each site, the deleted leader shoots left no marks among normal lateral branches (Fig. 7A). Similar structures were also observed in the winter buds of 2015 at the top of the main axis, where normal lateral buds with completely deleted apical buds were sometimes observed (Fig. 7B). These observations demonstrated that the deletion of leader shoots probably resulted from the deletion of apical buds at an early stage of their development, independently of the formation of lateral buds.

  1. In this study, significant increases in the morphological defects were shown in Japanese fir populations growing in areas near the F1NPP. The occurrence corresponded to the radioactive contamination level represented by the ambient dose rate in each site, suggesting that the defects could be due to the exposure to ionizing radiation from the radionuclides released after the accident.
    On the other hand, deletion of leader shoots was also observed in the control site at a lower frequency, indicating that the defects were not radiation-specific, but universal. The deletion of leader shoots in the control site occurred randomly in the annual whorls and not specifically in a certain year. Moreover, even in the highly contaminated sites, a low frequency of defects was observed before the F1NPP accident in 2011. These results suggested that the defects could also occur independently of radiation exposure.
    Similar defects of the main axis have been reported in many coniferous species grown in plantations and involve the separation of trunk into two or more stems of similar size, which is called a forking defect14,15,16,17. Forking defects can be caused by breakage of the leader shoot due to an accidental damage, such as bird perching, animal attack, wind damage, and pathogenic disease, or due to environmental stress such as frost14. Previous studies have shown that in lodgepole pine (Pinus contorta), the forking defects could also be caused by physiological control of apical dominance even in the absence of mechanical damage14,15. In this study, the observed forking defects in Japanese fir were identical to those in other coniferous tree species.
    In relation to radiation effects, deletion of the leader shoots has been reported in Scots pine trees chronically exposed to radiation in a contaminated area close to the Chernobyl nuclear power plant11. The trees that showed forking defects with deletion of annual leader shoots eventually formed bushy canopies without a main axis. Another study showed that Scots pine trees in Chernobyl were characterized by the disappearance of a single trunk and replacement with two or more trunks or branches, corresponding to the estimated dose rate during the development of apical buds12. Although the defects in pine trees close to the Chernobyl nuclear power plant were not all identical to the defects observed in Japanese fir trees in the area close to the F1NPP, the information seems to support the relationship between the morphological changes in Japanese fir and the chronic exposure to radiation from released radionuclides.
    Despite the correlation between the defects in Japanese fir and the radioactive contamination level, there is little biological information to support the contention that the increased frequencies of the morphological changes were due to radiation released after the F1NPP accident. Even though the damage at the early stage of apical bud formation is suggested as the main cause of the deletion of leader shoots, there was an inexplicable 2-year time lag between 2011, the year with the highest radiation dose in the environment, and 2013, the year with the highest frequency of defects. Consequently, processes at the cellular and tissue level involved in the deletion of leader shoots need to be elucidated in relation to the development of lateral and apical buds in coniferous plants.
    As described above, there are several factors that are possibly responsible for increased frequencies of the morphological defect observed in Japanese fir populations near the F1NPP, and, at present, there is no decisive evidence that any single factor is causally related to these increased frequencies. However, a positive correlation was observed between ambient dose rates and frequencies of the morphological defect, and these frequencies increased after the F1NPP accident while they were much lower before the accident, suggesting that, of several potential factors, ionizing radiation is most likely to have increased frequencies of the morphological defect. To confirm this contention, dose rates to Japanese fir should be estimated in contaminated fields of Fukushima, and effects of long-term irradiation on this tree should be investigated in irradiation facilities.


    Plant and field observations

    Samples of Japanese fir were examined in 4 sites (3 observation sites and 1 control site) in the Abukuma region dominated by the Abukuma Highlands and a series of gentle hills leading to a narrow plain along the east coast of Pacific Ocean (Fig. 2, Table 1). Climate conditions in this region are commonly cold with little snow during the winter. The vegetation in the examined sites was mostly mixed forests of Japanese fir trees with other dominant trees such as Japanese red pine (Pinus densiflora), and oak (Quercus serrata) (Table 1). The investigation of fir trees was performed between January 5 and 9, 2015, approximately 4 years after the F1NPP accident in March 2011. At the time of investigation, fir trees were in their dormant season when each branch has apical and lateral buds at the top (Fig. 1).
    All the fir trees between 0.4 m and 5 m in height were observed within 8–12 quadrats (10 × 10 m) placed in each examined site. Five whorls from the top of the main axis were observed. The occurrence of deleted leader shoots and the number of lateral branches were determined in each of annual whorl. The counts and the number in all the quadrats within each site were pooled before analysis.

    Measurement of ambient dose rate

    The ambient dose rate was measured at the centre and corners within each quadrat at 1 m above ground level with either an ionization chamber-type survey meter (ICS-323C, Hitachi Aloka Medical, Tokyo) for S1 or a NaI scintillation survey meter (TCS-172, Hitachi Aloka Medical, Tokyo) in S2, S3, and S4. The measurements were averaged within each site to determine the representative value of the ambient dose rate in the site.

    Statistical analysis

    Data were analyzed using Excel 2007. Comparisons between the groups were performed using Fisher’s exact test or the Chi-squared test.

    Additional Information

    How to cite this article: Watanabe, Y. et al. Morphological defects in native Japanese fir trees around the Fukushima Daiichi Nuclear Power Plant. Sci. Rep. 5, 13232; doi: 10.1038/srep13232 (2015).