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SpeecheSevere Nuclear Power Plant Accident in Japan
-- A medical doctor’s perspective --

Dr. SAITO Osamu

M.D. at Watari Hospital (Fukushima)/

Representative Director, Japan Council against A and H Bombs (Gensuikyo)



1.      Introduction

The accident at the Fukushima Daiichi Nuclear Power Plant on March 11, 2011 was caused by the Great East Japan Earthquake (Magnitude 9.0) and the onslaught of giant tsunamis that followed. Although the accident was caused as a direct consequence of the natural disaster, many people in Japan recognize that it was actually a human-made disaster.

Given the developments starting from the introduction of nuclear power generation in Japan up to the Fukushima disaster, and the government’s failure to respond properly after the accident, we must say that the future threat posed by the nuclear power industry to people’s safety is growing even further. This is because responsibility for nuclear accidents is not clearly stipulated by domestic law and, as a result, there is a continuing state of government inaction.

As a medical doctor, over the past four and a half years I have observed the physical conditions, minds and family life of the victims.


2. Introduction of nuclear power generation industry to Japan

   The first people in the world to experience the effect of the enormous energy released by nuclear fission were those of Hiroshima and Nagasaki in 1945. Then in March 1954, the U.S. conducted a hydrogen bomb test in Bikini Atoll in the Marshall Islands in the Pacific. The crewmembers of a Japanese tuna fishing boat operating in that area were exposed to the deadly fallout, and 6 months later the chief radio operator of the ship died from radiation sickness. We call this incident the Bikini tragedy, or the Fifth Lucky Dragon Incident, taken from the name of the ship. Within Japan, this incident reminded people of the tragedy of the atomic bombing 9 years before and triggered the birth and rapid growth of a movement calling for the prevention of nuclear war and the abolition of nuclear weapons. Japanese people’s strong feelings of rejection toward nuclear weapons is based on these painful experiences.

Strangely however, in the month following the Bikini disaster (April 1954), a national budget of about 250 million yen for introducing nuclear power generation was adopted. The introduction of a nuclear power industry could not have been possible without a strong push from the United States, which tried to sell its nuclear reactors and technology to Japan. On the other hand, the government of Japan was attracted to nuclear power generation as a major source of energy production for reviving Japan’s industries in the wake of its defeat in World War II.

The government gave great publicity to nuclear power generation, referring to it as the “peaceful use of the atom”, and took every financial support measure to suppress resistance to nuclear power stations from the candidate host communities. Further, to promote the nuclear power industry, it helped create a giant community of interest, made up of electric power businesses, nuclear researchers and the Ministry of Economy, Trade and Industry (METI). The key to this strategy was to establish a “Myth of Safety” by lavishly publicizing that nuclear power plants were absolutely safe.   

In short, the introduction of nuclear power in Japan has been promoted by the combined strength of political, intellectual and financial forces, pressuring people to accept it. In all this, dialogue between the government and the people regarding the safety of nuclear power was non-existent.      


3. Accident at the Fukushima Daiichi Nuclear Power Plant

In the wake of the Chernobyl disaster (1986), in 1996 the International Atomic Energy Agency (IAEA) set out a new concept of “Defense in Depth”. It proposed measures for the Fourth level of defense, in preparation for an unexpected accident going beyond an accident involving the structure of the reactor. It further proposed a Fifth level of defense in case of failure of measures in the previous level. The basic principle of the concept is that, however low the probability of damage to a reactor and radiation release to the atmosphere may be, severe damage to a reactor core and massive release of radiation is something that “will happen”.

Japan is a land of frequent earthquakes with many experiences of massive tsunami disasters in its history. Even in the last 30 years alone, we had the 1983 Middle Japan Sea Earthquake (Magnitude 7.7) with a maximum tsunami height of 40 meters, the 1993 South West off Hokkaido Earthquake (M. 7.8) with maximum tsunami height of 30.6m, and the recent 2011 Great East Japan Earthquake (M. 9.0) with a 40.1-meter tsunami. In addition to the onslaught of tsunamis on each occasion the underground fault surface slipped, causing ground uplifts and subsidence of some 50-70 centimeters stretching over 50-70 meters.    

However in Japan, for a long time, consideration was only given up to the Third level of defense: i.e., possible accidents arising from events occurring inside nuclear reactors were considered, but those which might arise from external factors were excluded from discussion of countermeasures. When a discussion was about to start within the Nuclear Safety Commission (of the Cabinet Office) in 2006 to review possible measures to accommodate the IAEA’s Defense in Depth proposal, it was the Nuclear and Industrial Safety Agency (NISA, belonging to METI), which was in charge of regulating nuclear safety, that blocked the review, saying, “Let sleeping dogs lie.”     

The political background to the government’s “let sleeping dogs lie” attitude was the fact that several lawsuits had been filed by citizens in different places over the safety of nuclear power plants, and such a revision in the government’s planning might work disadvantageously to the defendant. This was in spite of the fact that both the Tokyo Electric Power Company (TEPCO) and NISA were aware of the possibility of a total loss of power-supply caused by giant tsunamis.     

Here, the difference between the positions of TEPCO, an electric power company wanting to underestimate the possibility of the outbreak of accidents, and that of NISA, an agency originally set up to strictly ensure the safety of nuclear power plants, disappeared. The official agency for regulation had become captive to the industry (electric power businesses) trying to promote nuclear power generation.    

The earthquake vibrations that occurred on March 11, 2011 stopped the transmission of power supply to the Fukushima Daiichi from outside. The ensuing tsunamis inundated the emergency diesel generators, thus causing all means of supplying electric power to the plants to be lost. Large scale aftershocks that continuously occurred after March 11 made it very difficult to take countermeasures to the accident smoothly.

On March 12, there was a hydrogen explosion at Reactor 1. Another hydrogen explosion occurred at Reactor 3 on March 14 and also at Reactor 4 on March 15, followed by a massive release of radioactive substances on that day from Reactor 2. It was this release of radioactivity from Reactor 2 that eventually dictated the overall situation of people’s exposure to radiation and soil contamination in Fukushima Prefecture.


4. Release of radioactive substances

   The total amount of radioactivity released by the Fukushima Daiichi nuclear power plant accident is estimated to be 900 PBq (Peta-Becquerel), calculated in terms of iodine. This is equivalent to one-sixth of that released by the Chernobyl accident. It was expected that out of a 2 million population of Fukushima Prefecture, if no one had been evacuated, about 360,000 people would have been exposed to external radiation beyond 5mSv (millisievert) annually.

   If divided up in terms of the level of soil contamination, the number of people and the amount of external exposure to radiation during one year following the accident would have been as follows (IRSN, May 23, 2011):

(1) 6,000KBq/km2 -- 30,000KBq/km2: 2,200 people: exposed to 100 - 500mSV

(2) 3,000KBq/m2 <  : 3,100 people: 50mSv <

(3) 1,000KBq/m2 <  : 21,100 people: 16mSv <

(4) 600KBq/m2 <   : 43,000 people: 10mSv <

(5) 300KBq/m2 <   : 292,000 people: 5mSv <

   Under the circumstances, 78,000 people evacuated from within a 20-kilometer radius of the Fukushima Daiichi nuclear power plant. From areas beyond a 20km radius but with an expected annual exposure of over 20mSv, 10,010 people evacuated. Including 58,510 people from a 20 - 30km radius, a total of 156,420 people left home by instruction of the government (Report by the Nuclear Accident Investigation Committee of the Diet, September 30, 2012). In addition, several tens of thousands of people evacuated from home voluntarily. The number of evacuees was comparable to the 116,000 who evacuated from the three most affected countries at the time of the Chernobyl accident (IAEA, 2005). As of March 2015, 4 years after the accident, there are still 118,974 people in evacuation away from home.  

   During these years, the deaths after evacuation reached 1,962, many of whom are elderly. This number, accounting for 1% of all evacuees, exceeds the number of deaths directly caused by the earthquake and tsunami (1,604). In the areas directed by the government to evacuate (difficult-to-return zone, restricted residence zone, zone in preparation for the lifting of the evacuation order, etc.), the soil decontamination work is undertaken directly by the government, but progress is extremely slow. Consequently, many of the evacuees continue to anguish over decisions about whether and when they should go back, or whether they should choose to permanently live in the areas to which they evacuated.                                 

   After the nuclear power plant accident, an official program was launched to estimate the external radiation exposure of the entire population (2.06 million) of Fukushima Prefecture. As of December 2014, the number of respondents is only 449,000, 21.8% of the total. The study of these replies indicated that 99.8% of those analyzed were exposed to less than 5mSv, while the maximum estimated radiation was 25mSv. Among the people who resided in the areas covered by the radioactive plume (which spread to the northwest of the Fukushima Daiichi NPP), 900 people were included within the range between 5mSv and 25mSv. In the areas hosting many evacuees, annual radiation dose is less than 3mSv. For example, in the capital Fukushima City, during 2014, 95.6% of the citizens were included among those exposed to less than 1mSv of radiation. However, many people in Fukushima continue to be concerned about possible health problems caused by exposure to low-level radiation.   

In the areas not designated for evacuation, in 36 cities/towns/villages including Fukushima City which were contaminated by the radioactive plume the government is conducting decontamination work using the national budget. As of the end of July 2015, 63.4% of people’s housing lands, 90.5% of public facilities and 35.5% of roads had been cleaned. But the contaminated soil, mud, leaves and plants stripped from the surface of the buildings and land are piled up and left in the corners of housing lands. While the future of the construction plan for facilities to collect and store these contaminated substances is completely unclear, these piles remain a source of fear and anxiety for the people.   


5. Setback suffered by agriculture and fishery

   When the contamination of the farm soil of the entire prefecture became clear, the agricultural industry of Fukushima suffered catastrophic damage. The permitted level of radioactivity in rice was set at less than 100 Bq/kilogram, and shipping of crops over that standard was suspended. At present, all crops of rice harvested in farmland that has been screened and cleared is below the designated radiation standard. As for the fishing industry, fishermen in Fukushima are still kept on provisional test operation, which restricts them from conducting full-scale operations in terms of the catching areas, depth and types of fish.   

As of March 2014 (3 years after the accident), the rate of reconstruction of agriculture in terms of cropping area was 30%, while that of fishing in terms of the number of operating fishing ports was also 30%. The rate of rehabilitation in terms of the number of workers in agriculture was 62%, and in fishery, 2%. The ongoing Trans-Pacific Partnership (TPP) negotiations are a big issue for the farmers of Fukushima. If, as a result of the TPP agreement, cheap agricultural imports should flood the domestic market, the agricultural industry of Fukushima will inevitably suffer a crushing blow. The path for rehabilitation after the nuclear power plant accident will be affected negatively by a variety of factors both domestically and internationally. 


6. Survey on the incidence of thyroid cancer

   Not only radioactive cesium but also the majority of the radioactive iodine was carried by the wind about 80 kilometers to the northwest of Fukushima Daiichi, and then flew southward. The amount of thyroid radiation exposure estimated from the soil contamination map of radioactive iodine is highest in the east-coast area of Fukushima Prefecture (in the vicinity of the nuclear power plants), followed by the central part of Fukushima. The lowest was the inland western part of Fukushima. Still, all of these regions are estimated to be within 50mSv.

The actual dose of radiation exposure of children, measured by the NaI scintillation survey meter, is included in (1) the report of the Nuclear Emergency Response Headquarters; (2) the report of Hirosaki University; and (3) another Hirosaki University report covering different groups. All of them indicate that the amount of thyroid exposure was low: (1) says 95.6% were under 10mSv with the highest dose for children shown at 45mSv; (2) says 79% of those surveyed were below 10mSv, with the highest being 23mSv; and (3) says 99.0% were below 10mSv, with 18mSv as the highest (among children) (Hosoda et al., Environment International, 61:73-76, 2013).

   The Fukushima Prefectural Office has been carrying out thyroid ultrasound examinations on some 360,000 citizens who were 18 years old or younger at the time of the earthquake disaster. The initial examination conducted over the first 3 years was completed 1 year behind the schedule on April 30, 2015. The number of examinees was 300,476, accounting for 81.7% of the target group. Among them, based on the fine-needle aspiration biopsy, 113 cases (0.04%) of thyroid cancer and suspected thyroid cancer were confirmed. Among 99 cases of surgical operations, there were 95 cases of papillary adenocarcinoma, 3 anaplastic adenocarcinoma and 1 benign nodule.

   Conducting such a sweeping thyroid ultrasound examination on all children, including those with no symptoms, is unprecedented in the world. There is no definitive conclusion as to whether the confirmed cases of thyroid cancer to date have been induced by radioactive iodine or not. The screening seems to have left the children and parents with life-long psychological and social anxiety.


7. Psychological problems of the evacuees

   A questionnaire conducted on 40,000 evacuees has revealed the mental health situation of the evacuees. The results from the most recent survey (reported in FY 2013), using the K6 scales (Kessler, 2002, USA) to check the state of depression, indicated that the rate of those who scored more than 13 points (recognized as a problem) was high in each generation group, averaging 11.6% overall, which was 4 times higher than the national average of 3%. 

The survey using the SDQ (Strength and Difficulties Questionnaire) scale, a behavioral screening method for children, also demonstrated that the rates of children with difficulties (scoring 16 points or above) was 1.5 times higher than the national average of 9.5%: 14.2% among 4-6 years olds; 14.7% of primary school students; and 13.2% of junior high school students. Since the time of the accident, the Cabinet Office has been continuing the survey on deaths related to the nuclear power plant accident, including those from suicides. The suicide cases have not stopped. The number of suicides was 10 in FY 2011, 13 in FY 2012, 23 in FY2013, 15 in FY2014 and in FY2015, already 11 have killed themselves as of today. Among the total of 72 people who committed suicide, 70% were from ages 20 to 69, while 30% were above 70 years old. The major reason for the suicides seems to be despair caused by the loss of future prospects and being ripped away from their homes. Also, many victims, accounting for 48.9% of the evacuees, suffer from the breakup of family life, as their families are forced to live separately in evacuation. We cannot doubt that the loss of family life and means to make a living is affecting many in choosing to end their lives. So the psychological problems (tendency towards depression) of the evacuees are not only from the fear of impacts from radiation, but also the loss of their will to live, caused by the insincere attitude and response of TEPCO in negotiating with the victims for the loss of their land, houses and other assets, as well as the government’s tacit acceptance of TEPCO’s behavior. The current coordinated moves of TEPCO and the Ministry of Trade, Economy and Industry aimed at terminating compensation payments and housing support are also seriously afflicting the victims.


8. Moves to restart operations of nuclear power plants in Japan

   In the aftermath of the Great East Japan Earthquake and the accident at TEPCO’s Fukushima Daiichi nuclear power plant, all 50 of Japan’s nuclear power stations came to a complete stop for about 2 years, mainly due to the need for geological surveys and fortification work on nuclear reactor facilities in order to meet the revised standards for NPP operations set up after the accident. During the period when all the nuclear power stations were stopped completely, no energy shortage problems arose. Among the Japanese people, the argument for the necessity of nuclear power generation is losing ground. However, on August 11, 2015, the government allowed Kyushu Electric Power Company to restart its Sendai Nuclear Power Plant located at the southern end of Kagoshima. The Sendai NPP is located in an area where there have been warnings of increasing volcanic activities. However, the government granted permission despite the total absence of sufficient planning to cope with a massive flood of evacuees in the event of a nuclear power plant accident. The restart of the Sendai NPP was forced through in spite of the fact that the IAEA’s 5-level “Defense in Depth” concept has not been fulfilled. 


9. Conclusion

The first severe nuclear power plant accident in Japan (INES Level 7) has taught us a lesson that once a nuclear power plant accident occurs, it causes extensive and severe damage. It also made us realize that the very low probability of external events that might damage nuclear reactors (such as earthquakes or tsunamis) does not secure the safety of nuclear reactors, but rather that the belief in their 100% probability (i.e., the understanding that they will happen) is essential in order to defend against them. However, even after the Fukushima Daiichi accident, the IAEA’s concept of the 5 levels of “Defense in Depth” has not been discussed thoroughly among the people, nor has the government referred to it. In the current situation where more than 100,000 evacuees are still suffering, and when both TEPCO and the government are not at all trusted by the victims, there can be no platform in our country on which we can discuss the concept of Defense in Depth.

Those who believe in the value of nuclear power generation truly exceeding other energy options are not at all in the majority.

The nuclear accident of Fukushima continues to leave important lessons for the people. //