Health Effects of the Fukushima Nuclear Disaster

Health Effects of the Fukushima Nuclear Disaster provides a multidisciplinary retrospective on the health consequences on the population the first decade after the Fukushima nuclear disaster. Sections 1 and 2 of the book begins with an introduction and an overview of the developments surrounding the Fukushima accident. Section 3 discusses topics such as the physical health impact of radiation exposure as well as diseases that resulted from long-term evacuation. Section 4 examines the psychological factors and the social impact of the disaster and how their combined influence affected the physical and mental wellness of the population. The book concludes with Section 5 which covers the mitigation strategy for treatment and care of psychological health issues resulting from the disaster. The book contains expert contributions from those who have first-hand experience in the recovery efforts and are still actively researching the impact of the disaster. Health Effects of the Fukushima Nuclear Disaster provides readers with a coherent, multi-dimensional narrative about the physical, psychosocial, and psychological aspects of the decade-long aftermath of the Fukushima nuclear disaster.

• Provides information based on evidence obtained through scientific methods such as long-term epidemiological surveys and case studies
• Examines the indirect health impact, especially psychosocial effects, caused by technological disasters like nuclear accidents
• Includes contributions from experts in the field who participated in the recovery efforts and are currently researching the health impact of the Fukushima disaster

• Language: English
• Publisher: Academic Press
• Release date: Apr 30, 2022
• ISBN: 9780128240991

Book preview

Section I

Development of Fukushima disaster

Chapter 1: Development of Fukushima disaster

Tomoyuki Kobayashia; Seiji Yasumurab    a Department of Disaster Psychiatry, Fukushima Medical University School of Medicine, Fukushima, Japan

b Department of Public Health, Fukushima Medical University School of Medicine, Fukushima, Japan

Abstract

This chapter describes the circumstances of the Fukushima Daiichi Nuclear Power Plant accident and its aftermath. On March 11, 2011, a massive earthquake and tsunami struck the Tohoku region of Japan, and the following day a hydrogen explosion occurred at the power plant. As a large amount of radioactive material was released, the government ordered an evacuation, which the municipalities managed. A lack of information caused distress among residents, about 150,000 of whom were evacuated. Since then, Fukushima Prefecture has conducted a long-term survey to track the health status of the residents, promote their future well-being, and determine the long-term effects of exposure to low-dose radiation on their health.

Keywords

Nuclear accidents; Great East Japan Earthquake; Radiation; Evacuations; Fukushima Health Management Survey

Accident

At 2:46 p.m. on March 11, 2011, an earthquake of magnitude 9.0 struck off the coast of Sanriku, Japan. The quake shook so hard and so long that it was impossible to remain standing; buildings collapsed, the earth thundered, and landslides occurred. The quake, which measured between 6 and 7 on the 7-point Japanese scale in Miyagi, Fukushima, Ibaraki, and Tochigi prefectures, spawned a vast tsunami (Japan Meteorological Agency, n.d.). The tsunami reached various parts of the Pacific Ocean side of Japan, mainly in the Tohoku and northern Kanto regions, with a height of more than five times that of the average Japanese man in Soma city, Fukushima Prefecture, and in Miyako city, Iwate Prefecture. The tsunami quickly engulfed cities and towns, swallowing people who had been unable to escape it. It swept away many buildings, even whole neighborhoods, and snarled trains into a tangled mess. Those who had reached higher ground could only watch as their cities and towns collapsed. Subsequent waves wreaked further damage, moving up the rivers and spreading the damage inland over a large area. Cars, household goods, and collapsed buildings were piled up in submerged disorder. Many fires broke out. More than 15,000 people were killed and a further 2500 went missing, mostly because of the tsunami, and more than 400,000 structures were damaged or destroyed (National Police Agency Emergency Disaster Security Headquarter, 2020).

The Great East Japan Earthquake spawned three disasters. Following the earthquake and tsunami came the nuclear power plant accident, the central topic of this book. The Fukushima Daiichi [Number 1] Nuclear Power Plant (FDNPP), the site of the accident, is located in the towns of Futaba and Okuma, Fukushima Prefecture, facing the Pacific Ocean to the east. In response to the earthquake, all the reactors in operation that day at the FDNPP were automatically shut down. As reported by the Tokyo Electric Power Company (TEPCO), the quake caused a loss of power to the site, and emergency diesel generators cut in to ensure a safe shutdown (Tokyo Electric Power Company, 2012). About 40 minutes after the earthquake, however, two huge tsunamis reached the plant. The entire main building area where the reactor and turbine buildings are located was inundated. With the exception of the emergency diesel generator in Unit 6, all power was lost. In response, at 3:42 p.m., the plant superintendent reported to government and emergency organizations that a specific event as defined in Section 1, Article 10 of the Act on Special Measures Concerning Nuclear Emergency Preparedness had occurred. In Unit 2, the reactor core isolation cooling system, which can supply emergency cooling water to reactors for a time, was manually activated, but as the power was lost, the operational status could not be confirmed, so the water supply condition was unknown. At 3:45 p.m., this was reported as a special event as stipulated in Section 1, Article 15 of the Act, and at 7:03 p.m., the Prime Minister issued a nuclear emergency situation declaration. The power plant was in darkness, status displays were dark, debris was scattered throughout, and roads were cut, making it extremely difficult to assess the situation and start recovery work. However, some of the status monitors, emergency fire pumps, and isolation condensers were recovered, and electricity and fire trucks were able to restore some control. If the containment vessel pressure is allowed to rise and the vessel bursts, a large amount of radioactive material can be released, so venting was attempted to reduce pressure by allowing some gas to be released. However, at 3:36 p.m. 0n March 12, a meltdown and a hydrogen explosion occurred in the Unit 1 reactor building. Although the response continued, explosions and fires were heard in the Unit 3 reactor building on March 14 and in the Unit 4 reactor building on March 15 (Fig. 1). As a result, a large amount of radioactive material was released.

Fig. 1

Fig. 1 Unit 3 at the FDNPP, with white smoke, on March 15, 2011. The building behind it is Unit 4. Photo by Tokyo Electric Power Company.

Radiation effects

Radioactive materials emit radiation. The radioactivity of a particular material is measured in becquerels (Bq; particles disintegrated per second): the material emits radiation as a result of disintegration. The greater the radioactivity, the more energy emitted by the material. The extent to which this affects a person depends on the distance from the material. The amount of radiation a person is exposed to (radiation exposure) is measured in sieverts (Sv; joules of energy per kilogram of body mass weighted by type of radiation and body part exposed).

As radiation is invisible and has no smell, it cannot be perceived by human senses. Radiation occurs as both charged particles and electromagnetic waves emitted from nuclei of various elements when an imbalance in the numbers of protons and neutrons in the nuclei makes them unstable. An unstable nucleus can become stable by releasing the extra energy. The material it belongs to will continue to emit radiation until it all reaches a stable state. As the radioactive content of the material decreases, the radioactivity becomes weaker, but the time period varies from seconds to billions of years, depending on the material.

Radiation exposure affects the human body, but its effects depend on the type of radiation, the parts exposed, and the degree of exposure. Radiation can be divided into particle radiation, in the form of alpha and beta rays, and electromagnetic radiation, in the form of gamma rays and x-rays. Alpha rays (protons) have a strong effect on the human body but do not penetrate far into the tissues. By external exposure, beta rays (electrons), which penetrate the skin and subcutaneous tissues, and gamma rays (high-energy photons), which penetrate deeply, are more problematic than alpha rays. On the other hand, internal exposure caused by the ingestion of radioactive materials is more likely to be a problem with alpha rays. Internal exposure occurs when radioactive materials are ingested or inhaled, absorbed through the skin or wounds, or administered as radiopharmaceuticals for medical treatment. The body remains exposed to radiation until the material is excreted from the body or decays with time.

The effects on the body also depend on the sensitivity to radiation and the ease of accumulation of the materials by the organs and the tissues of the body. In the case of external exposure to beta rays, for example, if a large amount of radioactive material adheres to the body surface and is not removed quickly, it may affect basal cells and capillary cells, which are highly sensitive to radiation, causing skin erythema and even alopecia. Gamma rays, which can reach the interior of the body, are more likely to affect the more sensitive internal organs, leading to dysfunction of organs and tissues. In the case of internal exposure, organs and tissues that are prone to accumulating radioactive materials will be exposed to higher doses, and if they are highly radiosensitive, the possibility of radiation-related effects is high. Since the Chernobyl nuclear accident, an increase in the number of thyroid cancers among children in Belarus and Ukraine has been attributed to the tendency for radioactive iodine to accumulate in the thyroid gland and the gland’s higher radiation sensitivity in children than in adults (Eckerman, Harrison, Menzel, & Clement, 2012).

The effects of radiation on the body are classified as deterministic or stochastic according to the amount of radiation. Deterministic effects occur after a large exposure to radiation, which can kill or cripple a large number of cells of organs and tissues, resulting in effects such as skin damage, reduced blood cell count due to reduced hematopoiesis, and, in the womb, fetal damage and mental retardation. Deterministic effects occur only after exposure above a threshold. Stochastic effects, in contrast, result from mutations in genes, which can cause cancer and genetic abnormalities. They are called stochastic because the probability of their occurrence is not zero even at low dose levels. Epidemiologically, at least, the relationship between exposure to radiation and development of cancer is confirmed to increase almost linearly with dose above about 150 mSv, but even below 150 mSv, radiation has a theoretical effect on the development of cancer.

Radiation effects on the body mostly involve damage to DNA. Cells are capable of repairing DNA damage; when DNA is corrupted, repair enzymes rush in to repair it. In the case of limited damage, repair is successful and the cells return to normal, but in the case of extensive damage, the repair can fail and the cells die or degenerate. If many cells die, there may be clinical signs, but if only one or two cells die, no organ or tissue dysfunction is found, as other cells can take their place (deterministic effects). However, DNA repairs are often incomplete, and accidental mutations can occur. Most mutated cells are rectified or deleted, but some can survive, and the accumulation of additional gene mutations or changes in the gene expression levels in their progeny cells increases the probability of cancer cells (stochastic effects). Whereas deterministic effects can produce clinical symptoms within a few weeks, stochastic effects require years to decades before symptoms are seen because multiple processes take place between exposure and the development of cancer.

Evacuation in early phase

The earthquake and tsunami cut off much of the communication in Fukushima Prefecture. In the absence of sufficient information, residents began to evacuate for protection from the invisible threat of the radiation (Fig. 2). A number of documents and interviews available to us reveal what happened during the disaster but are often inconsistent with each other, illustrating the confusion at the time.

Fig. 2

Fig. 2 Evacuation paths of nine cities in the evacuation zone.

Before the Unit 1 reactor meltdown, the municipal offices were busy dealing with the aftermath of both the earthquake and the tsunami (Figs. 3 and 4). Administrators immediately began to assess the damage and guide the evacuation. To disseminate emergency response advice and help with evacuation, firefighters and disaster management staff drove to the coast in public information vehicles. As major aftershocks and tsunamis continued to hit, buildings were collapsing, roads were cracking, and the power and water supplies were cut off. Some emergency workers did not come back. Meanwhile, tsunami evacuees gathered at schools and other shelters, where municipal office staff registered them.

Fig. 3

Fig. 3 Namie town suffered extensive damage; March 12, 2011. Photo by The Fukushima Minpo Newspaper Publishing Company.

Fig. 4

Fig. 4 Volunteer firefighters carry victims found in the rubble in Minamisoma city, March 12, 2011. Photo by the Fukushima Minyu Shimbun.

In natural disasters, the primary source of information is local, but nuclear accidents are monitored centrally. If an emergency is detected at a TEPCO power plant, the information is sent to TEPCO’s head office and the government in Tokyo (Articles 10 and 15 of the Act), and then to the prefectural and municipal governments where the power plant is located. However, the earthquake and tsunami crippled communications in Fukushima Prefecture. Most phone lines were cut, and only a few remained connected. The city’s Internet and disaster radio systems were off. Moreover, the mobile phone service was not available in many areas, and even where it was available, the back-up batteries in the base stations slowly went flat, and the service was gradually lost. The only way to get any information was to use an emergency power source to run televisions and radios, but government officials could not broadcast all the time as they had to run the emergency response.

Disruptions and obstacles caused by the earthquake and tsunami also occurred in the national government and other bodies. Government structure in a nuclear disaster is defined in detail in the Act on Special Measures Concerning Nuclear Emergency Preparedness, the Basic Plan for Emergency Preparedness, and the Nuclear Emergency Response Manual. The manual defines the main organizations that respond to a nuclear disaster as the Nuclear Emergency Response Headquarters (NERHQ) and the Local Nuclear Emergency Response Headquarters (Local NERHQ) of the national government. If the Prime Minister issues a nuclear emergency situation declaration, the NERHQ, of which the Prime Minister is the director-general, is established in the Cabinet Office, and the Local NERHQ is established at an offsite center. The Local NERHQ, which is delegated some of the authority of the director-general of the NERHQ, responds to the accident such as by issuing evacuation orders with the support of the NERHQ and the support and cooperation of local governments and other organizations. However, the earthquake disrupted most of the circuits of terrestrial communication in Fukushima Prefecture. Consequently, communication among the government and Fukushima Prefecture’s NERHQ (Prefectural NERHQ), the offsite center, and other institutions in the prefecture became extremely hard. General communication lines, including the mobile phone network, also experienced congestion in Tokyo owing to the surge in traffic immediately following the earthquake. Disaster priority circuits were strained, and communication among the agencies that relied on them was far from smooth. The earthquake also impaired and congested road and rail networks, significantly impeding traffic movement from Tokyo to Fukushima Prefecture and within the prefecture. Consequently, there was a long delay in setting up the offsite center.

In accordance with the Basic Plan for Emergency Preparedness and the Fukushima Prefecture Disaster Prevention Plan, the prefecture had set up 24 monitoring posts in the prefecture to collect data for the prefecture’s Environmental Radioactivity Monitoring Center and published the data on its website. However, four of the 24 monitoring posts were swept away in the tsunami and another 19 lost their connection. Only one monitoring post remained working, so it was almost impossible for the government and Fukushima Prefecture to monitor atmospheric radiation doses. Although portable monitoring posts were set up beginning on March 12, the interruption of the mobile phone network and fuel shortages meant that it was not initially able to function properly. Therefore, owing to the disruption of the Local NERHQ and the inability to collect and share information, the secretariat of the NERHQ was delayed in considering and implementing a response to the accident.

Even though the Fukushima Prefectural Office was not affected by the tsunami, its main building was rendered unusable by the earthquake, and the office was moved to an alternative site to establish the Prefectural NERHQ. But as there was no adequate disaster response radio there, communications with the national government, municipalities, and disaster response agencies were fragile, making progress updates difficult. According to the official report of the Fukushima Nuclear Accident Independent Investigation Commission (National Diet of Japan Fukushima Nuclear Accident Independent Investigation Commission, 2012b), the prefectural government did not get the nuclear emergency situation declaration, which was issued at 7:03 p.m., until about an hour and a half later. But the Prefectural NERHQ was gathering information from TEPCO and was aware of the worsening situation at the FDNPP.

The prefectural government was aware that it did not have a clear legal basis for issuing evacuation orders, but alarmed by the slow pace of evacuation instructions from the national government, at 8:50 p.m., it issued an evacuation order for residents within a 2-km radius of the FDNPP. After the announcement at a press conference, prefectural police and firefighter radios were used to inform municipalities and residents about the evacuation. However, the extensive damage to equipment in some town and village offices made it extremely difficult to communicate. At 9:23 p.m., the Japanese government issued an evacuation order to residents within a 3-km radius of the FDNPP, and ordered residents within a 3–10-km radius of the plant to shelter indoors. These orders were conveyed mostly by the media, including TV.

TEPCO employees were dispatched to four towns–Naraha, Tomioka, Okuma, and Futaba (and nowhere else)–to explain the situation. But without sufficient expertise, the employees were unable to explain the full import of the danger. Okuma, for example, one of the towns where the plant is located, had relatively stable communication circuits and received evacuation orders from the national and prefectural governments. Nonetheless, with their attention focused on the tsunami and the search for missing persons scheduled to start the next morning (Sasaki, 2013), the residents did not comprehend the enormity of the danger.

In the absence of detailed information, the national government quickly expanded the evacuation zone. At 05:44 a.m. on March12, the order to evacuate within a 10-km radius of the plant was issued. Every municipality needed to evacuate its own residents and negotiated and secured its own shelters. Even through the evacuation orders were based on the distance from the power plant, many municipalities issued community-wide evacuation orders to encourage collaboration among residents. Some people left in their own vehicles, but many elderly or immobile residents–between several hundred and several thousand people, depending on the size of the town or village–left with municipal staff in buses and other vehicles. Long lines of cars were formed along the roads to the shelters. As the residents began to leave, the Unit 1 and Unit 3 reactors suffered meltdowns. The government’s evacuation zone was extended at 5:39 p.m. on the same day to a 10-km radius from the Daini [Number 2] Plant, in the towns of Naraha and Tomioka, 11.5 km from Daiichi, and at 6:25 p.m. to a 20-km radius of the Daiichi Plant (Fig. 5).

Fig. 5

Fig. 5 Lines of vehicles evacuating from coastal areas in Tomioka town, March 12, 2011. Photo by The Fukushima Minpo Newspaper Publishing Company.

On the night of March 11, following the earthquake and tsunami, more than 1000 residents of Naraha town, near the Fukushima Daini NPP, were evacuated to shelters within the town, some without blankets or food (Naraha-machi, 2014). The evacuation order for a 3-km radius issued at 9:23 p.m. did not cover all of Naraha, but the town authorities expected that it would be extended. At 7 a.m. the next morning, the disaster response headquarters in Naraha and Tomioka extended the zone to 30 km and asked Iwaki city, 30 km away, to accept the evacuees because it was impossible to predict the spread of radioactive materials on the wind and because the roads would be congested. At 8 a.m., the town authorities issued the order to evacuate the whole town. The staff and volunteer firefighters used public information vehicles to tell the residents to evacuate. Buses were used to relay children and the elderly first. Those who had their own transport were asked to go to designated shelters. By 4 p.m. that day, 7700 residents had left. In the shelters in Iwaki, water was still cut off and there was a lack of information because television coverage was limited. An increasing number of elderly people were especially suffering from respiratory symptoms. There were shortages of medicines, masks, blankets, kerosene, and other supplies, and the need for dialysis services and toilets for the disabled was identified. About 1000 residents of Naraha town then moved to Aizumisato town, with which it had originally had a sister city relationship, about 100 km away. Some evacuees were later taken by relatives and friends to other parts of the prefecture.

Kawauchi village, more distant from the power plant, gathered its own information and elected to evacuate. The earthquake moderately damaged about 20 buildings (Imai, 2014). The tsunami was not a threat. However, at around 7 a.m. on March 12, the village’s mayor received a phone call from the mayor of neighboring Tomioka town with a request to take in residents from there because the situation at the plant was worsening (Tomioka-machi, 2015) (Fig. 6). Kawauchi immediately accepted the evacuees and opened 17 shelters, including elementary and junior high schools. Evacuees were already arriving. From Tomioka, 6000 people arrived in Kawauchi, with a population of fewer than 3000. Relief supplies such as blankets and stoves were in short supply. At this point, Kawauchi did not consider the situation dire. That perception changed, however, on March 14, when the Unit 3 reactor exploded, and on March 15, when the Unit 4 reactor also exploded. Several villagers who worked at the plant had recommended that it was time to evacuate. At 7 a.m. on March 16, the village mayor ordered the whole village and the evacuees from Tomioka to evacuate. He called the director of the largest convention center in Fukushima Prefecture, Big Palette Fukushima, and got approval to send the evacuees there, as it was one of the largest shelters at the time. So 1300 residents of Tomioka and 700 residents of Kawauchi took shelter there.

Fig. 6

Fig. 6 Residents heading out of town with their luggage from Tomioka, March 12, 2011. Photo by The Fukushima Minpo Newspaper Publishing Company.

Confusion reigned in both evacuated municipalities and refuge municipalities. Despite being devastated by the tsunami and the considerable confusion, Soma city did not evacuate, and instead it tried to accept as many evacuees as possible (Fig. 7). At 2:30 a.m. on March 12, it already housed 3849 survivors in 24 shelters. That night, evacuees began to arrive in the city, especially from Minamisoma city. Yet it had only about 200 blankets, there was a very high number of deaths, and numbers of coffins and cremations were restricted. The city compiled detailed reports of the situation and of the actions taken (Soma City Earthquake Response Headquarter, 2011). Staff asked to stop accepting evacuees from Minamisoma after 800, which they considered the maximum capacity. Mental health medications started to run out and the hospital was inundated with patients. Logistic companies were reluctant to come into the city, and supplies were scarce. Although Soma city is more than 30 km from the FDNPP, tensions persisted owing to the elevated atmospheric radiation dose in Iitate village, which is at a similar distance.

Fig. 7

Fig. 7 Soma city, where fire broke out after buildings were swept away by the tsunami, March 11, 2011. Photo by the Fukushima Minyu Shimbun.

The lack of information caused distress. About 150,000 residents of Fukushima Prefecture were evacuated on order of the government (Figs. 8 and 9). However, only 20% of the residents in towns near the plant knew about the conditions at the plant when the order was given to evacuate within a 10-km radius (National Diet of Japan Fukushima Nuclear Accident Independent Investigation Commission, 2012a). In the shelters, digital broadcasts (1seg), car radios, and mobile phones were valuable sources of information for the evacuees. However, the mobile phone network gradually failed. Many residents had heard the evacuation orders on the municipality’s emergency radios but had not heard about the severity of the accident or the expected evacuation period. A number of evacuees anticipated that the evacuation would last a few days and left with little more than the clothes on their backs. Some were evacuated to what were later determined to be high-dose areas. Some evacuees had to move several times. These problems created anxiety. Hospitals and nursing homes within a 20-km radius had a hard time securing shelters and safe transport, and at least 60 patients died by the end of March.

Fig. 8

Fig. 8 Survivors helping each other in shelters in Kawamata town, March 13, 2011. Photo by The Fukushima Minpo Newspaper Publishing Company.

Fig. 9

Fig. 9 Sick evacuees being carried out in a shelter in Kawamata town, March 13, 2011. Photo by The Fukushima Minpo Newspaper Publishing Company.

On March 15, residents within a radius of 20–30 km were ordered to shelter indoors. However, prolonged evacuation put a strain on lifelines and destroyed life infrastructure. Consequently, on March 25, residents were asked to evacuate. Once again, little information was provided by the government to help the residents decide whether they