A natural disaster is a major adverse event resulting from natural processes of the Earth; examples include floods, volcanic eruptions, earthquakes, tsunamis, and other geologic processes. A natural disaster can cause loss of life or property damage, and typically leaves some economic damage in its wake, the severity of which depends on the affected population's resilience, or ability to recover.[1]
An adverse event will not rise to the level of a disaster if it occurs in an area without vulnerable population.[2][3][4] In a vulnerable area, however, such as San Francisco, an earthquake can have disastrous consequences and leave lasting damage, requiring years to repair.Earthquakes
Main article: Earthquake
See also: List of earthquakes
The 1693 Sicily earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. At the Earth's surface, earthquakes manifest themselves by vibration, shaking and sometimes displacement of the ground. The vibrations may vary in magnitude. Earthquakes are caused mostly by slippage within geological faults, but also by other events such as volcanic activity, landslides, mine blasts, and nuclear tests. The underground point of origin of the earthquake is called the focus. The point directly above the focus on the surface is called the epicenter. Earthquakes by themselves rarely kill people or wildlife. It is usually the secondary events that they trigger, such as building collapse, fires, tsunamis (seismic sea waves) and volcanoes, that are actually the human disaster. Many of these could possibly be avoided by better construction, safety systems, early warning and planning. Some of the most significant earthquakes in recent times include: The 2004 Indian Ocean earthquake, the third largest earthquake recorded in history,registering a moment magnitude of 9.1-9.3. The huge tsunamis triggered by this earthquake killed at least 229,000 people.
The 2011 Tōhoku earthquake and tsunami registered a moment magnitude of 9.0. The death toll from the earthquake and tsunami is over 13,000, and over 12,000 people are still missing.
The 8.8 magnitude February 27, 2010 Chile earthquake and tsunami cost 525 lives.[6]
The 7.9 magnitude May 12, 2008 Sichuan earthquake in Sichuan Province, China. Death toll at over 61,150 as of May 27, 2008.
The 7.7 magnitude July 2006 Java earthquake, which also triggered tsunamis.
The 6.9 magnitude 2005 Azad Jammu & Kashmir and KPK province Earthquake, which killed or injured above 75,000 people in Pakistan.
Volcanic eruptions
Main articles: List of largest volcanic eruptions and Types of volcanic eruptions
Artist's impression of the volcanic eruptions that formed the Deccan Traps in India.
Volcanoes can cause widespread destruction and consequent disaster in several ways. The effects include the volcanic eruption itself that may cause harm following the explosion of the volcano or the fall of rock. Second, lava may be produced during the eruption of a volcano. As it leaves the volcano, the lava destroys many buildings and plants it encounters. Third, volcanic ash generally meaning the cooled ash - may form a cloud, and settle thickly in nearby locations. When mixed with water this forms a concrete-like material. In sufficient quantity ash may cause roofs to collapse under its weight but even small quantities will harm humans if inhaled. Since the ash has the consistency of ground glass it causes abrasion damage to moving parts such as engines. The main killer of humans in the immediate surroundings of a volcanic eruption is the pyroclastic flows, which consist of a cloud of hot volcanic ash which builds up in the air above the volcano and rushes down the slopes when the eruption no longer supports the lifting of the gases. It is believed that Pompeii was destroyed by a pyroclastic flow. A lahar is a volcanic mudflow or landslide. The 1953 Tangiwai disaster was caused by a lahar, as was the 1985 Armero tragedy in which the town of Armero was buried and an estimated 23,000 people were killed .
A specific type of volcano is the supervolcano. According to the Toba catastrophe theory 75,000 to 80,000 years ago a super volcanic event at Lake Toba reduced the human population to 10,000 or even 1,000 breeding pairs creating a bottleneck in human evolution.[7] It also killed three quarters of all plant life in the northern hemisphere. The main danger from a supervolcano is the immense cloud of ash which has a disastrous global effect on climate and temperature for many years.
Hydrological disasters
Main article: Hydrological disasters
It is a violent, sudden and destructive change either in quality of earth's water or in distribution or movement of water on land below the surface or in atmosphere.
Floods
Main article: flood
See also: List of Floods
A flood is an overflow of an expanse of water that submerges land.[8] The EU Floods directive defines a flood as a temporary covering by water of land not normally covered by water.[9] In the sense of "flowing water", the word may also be applied to the inflow of the tide. Flooding may result from the volume of water within a body of water, such as a river or lake, which overflows or breaks levees, with the result that some of the water escapes its usual boundaries.[10] While the size of a lake or other body of water will vary with seasonal changes in precipitation and snow melt, it is not a significant flood unless the water covers land used by man like a village, city or other inhabited area, roads, expanses of farmland, etc.
The Limpopo River, in southern Mozambique, during the 2000 Mozambique flood
Some of the most notable floods include:
The Johnstown Flood of 1889 where over 2200 people lost their lives when the South Fork Dam holding back Lake Conemaugh broke.
The Huang He (Yellow River) in China floods particularly often. The Great Flood of 1931 caused between 800,000 and 4,000,000 deaths.
The Great Flood of 1993 was one of the most costly floods in United States history.
The North Sea flood of 1953 which killed 2251 people in the Netherlands and eastern England
The 1998 Yangtze River Floods, in China, left 14 million people homeless.
The 2000 Mozambique flood covered much of the country for three weeks, resulting in thousands of deaths, and leaving the country devastated for years afterward.
The 2005 Mumbai floods which killed 1094 people.
The 2010 Pakistan floods, damaged crops and infrastructure, claiming many lives.
Tropical cyclones can result in extensive flooding and storm surge, as happened with:
Bhola Cyclone, which struck East Pakistan (now Bangladesh) in 1970,
Typhoon Nina, which struck China in 1975,
Hurricane Katrina, which struck New Orleans, Louisiana in 2005, and
Cyclone Yasi, which struck Australia in 2011
Limnic eruptions
Main article: Limnic eruption
A cow suffocated by gases from Lake Nyos after a limnic eruption
A limnic eruption occurs when a gas, usually CO2, suddenly erupts from deep lake water, posing the threat of suffocating wildlife, livestock and humans. Such an eruption may also cause tsunamis in the lake as the rising gas displaces water. Scientists believe landslides, volcanic activity, or explosions can trigger such an eruption. To date, only two limnic eruptions have been observed and recorded:
In 1984, in Cameroon, a limnic eruption in Lake Monoun caused the deaths of 37 nearby residents.
At nearby Lake Nyos in 1986 a much larger eruption killed between 1,700 and 1,800 people by asphyxiation.
Tsunami
Main article: Tsunami
Tsunamis can be caused by undersea earthquakes as the one caused by the 2004 Indian Ocean Earthquake, or by landslides such as the one which occurred at Lituya Bay, Alaska.
The 2004 Indian Ocean Earthquake created the Boxing Day Tsunami.
On March 11, 2011, a tsunami occurred near Fukushima, Japan and spread through the Pacific.
Meteorological disasters
Main article: Meteorological disasters
Young steer after a blizzard, March 1966
Blizzards
Main article: Blizzard
Blizzards are severe winter storms characterized by heavy snow and strong winds. When high winds stir up snow that has already fallen, it is known as a ground blizzard. Blizzards can impact local economic activities, especially in regions where snowfall is rare.
Significant blizzards include:
The Great Blizzard of 1888 in the United States in which many tons of wheat crops are destroyed.
The 2008 Afghanistan blizzard
The North American blizzard of 1947
The 1972 Iran blizzard resulted in approximately 4,000 deaths and lasted for 5 to 7 days.
Cyclonic storms
Tropical Cyclones
Hurricane Katrina
Main articles: Tropical Cyclone and Cyclone
See also: List of tropical cyclones
Cyclone, tropical cyclone, hurricane, and typhoon are different names for the same phenomenon a cyclonic storm system that forms over the oceans. The deadliest hurricane ever was the 1970 Bhola cyclone; the deadliest Atlantic hurricane was the Great Hurricane of 1780 which devastated Martinique, St. Eustatius and Barbados. Another notable hurricane is Hurricane Katrina which devastated the Gulf Coast of the United States in 2005.
Extratropical Cyclones
Main article: Extratropical cyclone
Extratropical cyclones, sometimes called mid-latitude cyclones, are a group of cyclones defined as synoptic scale low pressure weather systems that occur in the middle latitudes of the Earth (outside the tropics) not having tropical characteristics, and are connected with fronts and horizontal gradients in temperature and dew point otherwise known as "baroclinic zones". As with tropical cyclones, they are known by different names in different regions (Nor'easter, Pacific Northwest windstorms, European windstorm, East Asian-northwest Pacific storms, Sudestada and Australian east coast cyclones). The most intense extratropical cyclones cause widespread disruption and damage to society, such as the storm surge of the North Sea flood of 1953 which killed 2251 people in the Netherlands and eastern England, the Great Storm of 1987 which devastated southern England and France and the Columbus Day Storm of 1962 which struck the Pacific northwest.
Droughts
Main article: Drought
On the outskirts of Dadaab, Kenya, during the 2011 East Africa drought.
Drought is unusual dryness of soil, resulting in crop failure and shortage of water for other uses, caused by significantly lower rainfall than average over a prolonged period. Hot dry winds, high temperatures and consequent evaporation of moisture from the ground can contribute to conditions of drought.
Well-known historical droughts include:
1900 India killing between 250,000 to 3.25 million.
1921-22 Soviet Union in which over 5 million perished from starvation due to drought
1928-30 Northwest China resulting in over 3 million deaths by famine.
1936 and 1941 Sichuan Province China resulting in 5 million and 2.5 million deaths respectively.
In 2006, states of Australia including South Australia, Western Australia, New South Wales, Northern Territory and Queensland had been under drought conditions for five to ten years. The drought is beginning to affect urban area populations for the first time. With the majority of the country under water restrictions.
In 2006, Sichuan Province China experienced its worst drought in modern times with nearly 8 million people and over 7 million cattle facing water shortages.
12-year drought that was devastating southwest Western Australia, southeast South Australia, Victoria and northern Tasmania was "very severe and without historical precedent".
In 2011, the State of Texas lived under a drought emergency declaration for the entire calendar year. The drought caused the Bastrop fires.
Hailstorms
Main article: Hail
Hailstorms are falls of rain drops that arrive as ice, rather than melting before they hit the ground. A particularly damaging hailstorm hit Munich, Germany, on July 12, 1984, causing about 2 billion dollars in insurance claims.
Heat waves
Main article: Heat wave
A heat wave is a period of unusually and excessively hot weather. The worst heat wave in recent history was the European Heat Wave of 2003.
A summer heat wave in Victoria, Australia, created conditions which fuelled the massive bushfires in 2009. Melbourne experienced three days in a row of temperatures exceeding 40°C (104°F) with some regional areas sweltering through much higher temperatures. The bushfires, collectively known as "Black Saturday", were partly the act of arsonists.
The 2010 Northern Hemisphere summer resulted in severe heat waves, which killed over 2,000 people. It resulted in hundreds of wildfires which causing widespread air pollution, and burned thousands of square miles of forest.
Tornadoes
Main article: Tornado
See also: List of tornadoes and tornado outbreaks
[icon] This section requires expansion. (December 2010)
A tornado is a violent, dangerous, rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is also referred to as a twister or a cyclone,[11] although the word cyclone is used in meteorology in a wider sense, to refer to any closed low pressure circulation. Tornadoes come in many shapes and sizes, but are typically in the form of a visible condensation funnel, whose narrow end touches the earth and is often encircled by a cloud of debris and dust. Most tornadoes have wind speeds less than 110 miles per hour (177 km/h), are approximately 250 feet (80 m) across, and travel a few miles (several kilometers) before dissipating. The most extreme tornadoes can attain wind speeds of more than 300 mph (480 km/h), stretch more than two miles (3 km) across, and stay on the ground for dozens of miles (perhaps more than 100 km).[12][13][14]
Well-known historical tornadoes include:
The Tri-State Tornado of 1925, which killed over 600 people in the United States;
The Daulatpur-Saturia Tornado of 1989, which killed roughly 1,300 people in Bangladesh.
Wildfires
Main article: Wildfire
See also: List of forest fires
Wildfires are large fires which often start in wildland areas. Common causes include lightning and drought but wildfires may also be started by human negligence or arson. They can spread to populated areas and can thus be a threat to humans and property, as well as wildlife.
Notable cases of wildfires were the 1871 Peshtigo Fire in the United States, which killed at least 1700 people, and the 2009 Victorian bushfires in Australia.
Health disasters
Epidemics
Main article: List of epidemics
The A H5N1 virus, which causes Avian influenza
An epidemic is an outbreak of a contractible disease that spreads through a human population. A pandemic is an epidemic whose spread is global. There have been many epidemics throughout history, such as the Black Death. In the last hundred years, significant pandemics include:
The 1918 Spanish flu pandemic, killing an estimated 50 million people worldwide
The 1957-58 Asian flu pandemic, which killed an estimated 1 million people
The 1968-69 Hong Kong water flu pandemic
The 2002-3 SARS pandemic
The AIDS pandemic, beginning in 1959
The H1N1 Influenza (Swine Flu) Pandemic 2009-2010
Other diseases that spread more slowly, but are still considered to be global health emergencies by the WHO, include:
XDR TB, a strain of tuberculosis that is extensively resistant to drug treatments
Malaria, which kills an estimated 1.6 million people each year
Ebola hemorrhagic fever, which has claimed hundreds of victims in Africa in several outbreaks
Space disasters
Fallen trees caused by the Tunguska meteoroid of the Tunguska event in June 1908.
Impact events
Main article: Impact event
[icon] This section requires expansion. (December 2010)
One of the largest impact events in modern times was the Tunguska event in June 1908.
Solar flares
Main article: Solar flare
A solar flare is a phenomenon where the sun suddenly releases a great amount of solar radiation, much more than normal. Some known solar flares include:
An X20 event on August 16, 1989[15]
A similar flare on April 2, 2001[15]
The most powerful flare ever recorded, on November 4, 2003, estimated at between X40 and X45[16]
The most powerful flare in the past 500 years is believed to have occurred in September 1859[17]
Gamma-ray burst
Main article: Solar flare
Gamma-ray bursts (GRBs) are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe.[18] Bursts can last from ten milliseconds to several minutes. The initial burst is usually followed by a longer-lived "afterglow" emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).
All the bursts astronomers have recorded so far have come from distant galaxies and have been harmless to Earth, but if one occurred within our galaxy and were aimed straight at us, the effects could be devastating. Currently orbiting satellites detect an average of about one gamma-ray burst per day. The closest known GRB so far was GRB 031203.[19]
Protection by international law
International law, for example Geneva Conventions defines International Red Cross and Red Crescent Movement the Convention on the Rights of Persons with Disabilities, requires that "States shall take, in accordance with their obligations under international law, including international humanitarian law and international human rights law, all necessary measures to ensure the protection and safety of persons with disabilities in situations of risk, including the occurrence of natural disaster."[20] And further United Nations Office for the Coordination of Humanitarian Affairs is formed by General Assembly Resolution 44/182. People displaced due to natural disasters are currently protected under international law (Guiding Principles of International Displacement, Campala Convention of 2009)[21]Effects of the Chernobyl disaster
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The 1986 Chernobyl disaster triggered the release of substantial amounts of radiation into the atmosphere in the form of both particulate and gaseous radioisotopes. It is the most significant unintentional release of radiation into the environment to date. It has been suggested that the radioactive contamination caused by the Chernobyl disaster greatly exceeded that of the atomic bombing of Hiroshima and Nagasaki in 1945.[citation needed]
The work of the Scientific Committee on Problems of the Environment (SCOPE), however, suggests that the two events cannot be directly compared through a single number, with one being simply x times larger than the other. This is partly due to the fact that the isotopes released at Chernobyl tended to be longer-lived than those released by the detonation of atomic bombs, thus producing radioactivity curves that vary in shape as well as size.[citation needed]
Contents [hide]
1 Human exposure to radiation
1.1 Dose to the general public within 30 km of the plant
2 Short-term health effects and immediate results
2.1 Workers and liquidators
2.2 Evacuation
2.3 Civilians
2.4 Plant and animal health
2.5 Suggested long-range effects
3 Long-term health effects
3.1 Science and politics: the problem of epidemiological studies
3.2 Caesium radioisotopes
3.3 25 years after the catastrophe
3.4 Effect on the natural world
3.5 Studies on wildlife in the Exclusion Zone
3.6 Chernobyl Forum report and criticisms
4 Controversy over human health effects
4.1 Chernobyl Forum report
4.2 TORCH report
4.3 Greenpeace
4.4 April 2006 IPPNW report
4.5 New York Academy of Sciences publication
4.6 2011 UNSCEAR report
4.7 Other studies and claims
4.8 French legal action
5 Comparisons to other radioactivity releases
6 See also
7 References
8 External links
Human exposure to radiation[edit]
According to a 2008 United Nations (UNSCEAR) report, the Chernobyl accident had by 2005 caused 0.065 million man-Sieverts (Sv) of radiation exposure to recovery workers and evacuees, 0.18 million man-Sv to the populace of the Ukraine, Belarus, and Russia, and a dose to most of the more distant European countries amounting to 0.13 million man-Sv. The same report estimated a further 25% more exposure would be received from residual radiosotopes after 2005.[1] The total global collective dose from Chernobyl was earlier estimated by UNSCEAR in 1988 to be "600,000 man Sv, equivalent on average to 21 additional days of world exposure to natural background radiation."[2]
Dose to the general public within 30 km of the plant[edit]
The inhalation dose (internal dose) for the public during the time between the accident and their evacuation from the area in what is now the 30 km evacuation zone around the plant has been estimated (based on ground deposition of caesium-137) to be between 3 and 150 mSv. This translates into between a 1 in 6700 and a 1 in 130 chance of developing a fatal cancer from this radiation. These figures are computed under the assumption that the ICRP risk factor of a 5% of a fatal cancer per Sv of exposure for adults (depending on the distance from the reactor and the day of evacuation). For one-year-old children, a dose estimate of between 10 and 700 mSv, equating to between a 1 in 2000 and a 1 in 30 chance of developing a fatal cancer, has been made.[3]
Thyroid doses for adults around the Chernobyl area were estimated to be between 20 and 1000 mSv, while for one-year-old infants, these estimates were higher, at 20 to 6000 mSv. For those who left at an early stage after the accident, the internal dose due to inhalation was 8 to 13 times higher than the external dose due to gamma /beta emitters. For those who remained until later (day 10 or later), the inhalation dose was 50 to 70% higher than the dose due to external exposure. The majority of the dose was due to Iodine-131 (about 40%) and tellurium and rubidium isotopes (about 20 to 30% for Rb and Te).[4]
The ingestion doses in this same group of people have also been estimated using the cesium activity per unit of area, isotope ratios, average day of evacuation, intake rate of milk and green vegetables, and what is known about the transfer of radioactivity via plants and animals to humans. For adults the dose has been estimated to be between 3 and 180 mSv, while for one-year-old infants, a dose of between 20 and 1300 mSv has been estimated. Again, the majority of the dose was thought to be mostly due to Iodine-131, and the external dose was much smaller than the internal dose due to the radioactivity in the diet.[5]
Short-term health effects and immediate results[edit]
The explosion at the power station and subsequent fires inside the remains of the reactor resulted in the development and dispersal of a radioactive cloud which drifted not only over Russia, Belarus, and Ukraine, but also over the European part of Turkey, Greece, Moldova, Romania, Bulgaria, Lithuania, Finland, Denmark, Norway, Sweden, Austria, Hungary, Czechoslovakia, Yugoslavia, Poland, Estonia, Switzerland, Germany, Italy, Ireland, France, and Corsica.,[6] Canada[7] and the United Kingdom (UK).[8][9] In fact, the initial evidence in other countries that a major exhaust of radioactive material had occurred came not from Soviet sources, but from Sweden, where on 27 April workers at the Forsmark Nuclear Power Plant (approximately 1100 km from the Chernobyl site) were found to have radioactive particles on their clothing.
It was Sweden's search for the source of radioactivity (after they had determined there was no leak at the Swedish plant) that led to the first hint of a serious nuclear problem in the Western Soviet Union. In France, the government then claimed that the radioactive cloud had stopped at the Italian border. Therefore, while some kinds of food (mushrooms in particular) were prohibited in Italy because of radioactivity, the French authorities took no such measures, in an attempt to appease the population's fears (see below).
Contamination from the Chernobyl disaster was not evenly spread across the surrounding countryside, but scattered irregularly depending on weather conditions. Reports from Soviet and Western scientists indicate that Belarus received about 60% of the contamination that fell on the former Soviet Union. A large area in Russia south of Bryansk was also contaminated, as were parts of northwestern Ukraine.
203 people were hospitalized immediately, of whom 31 died (28 of them died from acute radiation exposure). Most of these were fire and rescue workers trying to bring the disaster under control, who were not fully aware of how dangerous the radiation exposure (from the smoke) was. (For a discussion of the more important isotopes in fallout see fission products.) 135,000 people were evacuated from the area, including 50,000 from the nearby town of Pripyat, Ukraine. Health officials have predicted that over the next 70 years there will be a 2% increase in cancer rates in much of the population which was exposed to the 5–12 EBq (depending on source) of radioactive contamination released from the reactor.
Soviet scientists reported that the Chernobyl Unit 4 reactor contained about 180–190 metric tons of uranium dioxide fuel and fission products. Estimates of the amount of this material that escaped range from 5 to 30 percent, but some liquidators, who have actually been inside the sarcophagus and the reactor shell itself (e.g. Mr. Usatenko and Dr. Karpan) state that not more than 5–10% of the fuel remains inside. Indeed, photographs of the reactor shell show that it is virtually empty.[citation needed] Because of the intense heat of the fire, and with no containment building to stop it, much of the ejected fuel was vaporized or particulized and lofted high into the atmosphere, where it spread.
Workers and liquidators[edit]
Soviet badge awarded to 600,000+ liquidators.
The workers involved in the recovery and cleanup after the disaster, called "liquidators", received high doses of radiation. In most cases, these workers were not equipped with individual dosimeters to measure the amount of radiation received, so experts can only estimate their doses. Even where dosimeters were used, dosimetric procedures varied - some workers are thought to have been given more accurate estimated doses than others.[citation needed] According to Soviet estimates, between 300,000 and 600,000 people were involved in the cleanup of the 30 km evacuation zone around the reactor, but many of them entered the zone two years after the disaster.[10]
Estimates of the number of "liquidators" vary; the World Health Organization, for example, puts the figure at about 800,000; Russia lists as liquidators some people who did not work in contaminated areas.[citation needed] In the first year after the disaster, the number of cleanup workers in the zone was estimated to be 211,000. These workers received an estimated average dose of 165 millisieverts (16.5 REM).
The plume of radioactive debris unleashed by the disaster at Chernobyl has been said[who?] to be approximately equal[vague] to the contamination that would occur from 400 Hiroshima bombs. Even if this is correct, it is difficult to usefully compare the two types of event. An atomic bomb delivers most of its radiation as a near-instantaneous burst of gamma-rays, followed by a much lesser dispersal of radioactive fallout consisting mainly of very short-lived radionuclides. A reactor explosion and fire, on the other hand, produces most of its contamination in the form of fallout, and this fallout, largely composed of melted or vaporised reactor fuel, tends to contain a much higher proportion of radionuclides with medium to long half-life. Levels of radioactivity in the vicinity of a recent atomic bomb blast thus rapidly diminish, while radioactive contamination from a Chernobyl-type accident is far more persistent.[11]
A sevenfold increase in DNA mutations has been identified in children of liquidators conceived after the accident, when compared to their siblings that were conceived before. However, this effect diminishes sharply with time.[11]
Evacuation[edit]
Map showing Caesium-137 contamination in the Chernobyl area as of 1996
Soviet authorities started evacuating people from the area around Chernobyl only on the second day after the disaster (after about 36 hours). By May 1986, about a month later, all those living within a 30 km (19 mi) radius of the plant (about 116,000 people) had been relocated. This area is often referred to as the zone of alienation. However, significant radiation affected the environment over a much wider scale than this 30 km radius encloses.
According to reports from Soviet scientists, 28,000 square kilometers (km ², or 10,800 square miles, mi²) were contaminated by caesium-137 to levels greater than 185 kBq per square meter. Roughly 830,000 people lived in this area. About 10,500 km ² (4,000 mi²) were contaminated by caesium-137 to levels greater than 555 kBq/m². Of this total, roughly 7,000 km² (2,700 mi²) lie in Belarus, 2,000 km² (800 mi²) in the Russian Federation and 1,500 km² (580 mi²) in Ukraine. About 250,000 people lived in this area. These reported data were corroborated by the International Chernobyl Project.[12]
Civilians[edit]
Some children in the contaminated areas were exposed to high radiation doses of up to 50 gray (Gy), mostly due to an intake of radioactive iodine-131 (a relatively short-lived isotope with a half-life of 8 days) from contaminated milk produced locally. Several studies have found that the incidence of thyroid cancer among children in Belarus, Ukraine, and Russia has risen sharply since the Cherobyl disaster. The International Atomic Energy Agency (IAEA) notes "1800 documented cases of thyroid cancer in children who were between 0 and 14 years of age when the disaster occurred, which is far higher than normal",[13] although this source fails to note the expected rate. The childhood thyroid cancers that have appeared are of a large and aggressive type but, if detected early, can be treated. Treatment entails surgery followed by iodine-131 therapy for any metastases. To date, such treatment appears to have been successful in the vast majority of cases.[citation needed]
Late in 1995, the World Health Organization (WHO) linked nearly 700 cases of thyroid cancer among children and adolescents to the Chernobyl disaster, and among these, some 10 deaths are attributed to radiation. However, the rapid increase in thyroid cancers detected suggests some of this increase may be an artifact of the screening process.[citation needed] Typical latency time of radiation-induced thyroid cancer is about 10 years, but the increase in childhood thyroid cancers in some regions was observed as early as 1987.
Plant and animal health[edit]
An exhibit at the Ukrainian National Chernobyl Museum. Birth defects rates are higher in contaminated areas.[14]
A large swath of pine forest killed by acute radiation was named the Red Forest. The dead pines were bulldozed and buried. Livestock were removed during the human evacuations.[15] Elsewhere in Europe, levels of radiation were examined in various natural foodstocks. In both Sweden and Finland, fish in deep freshwater lakes were banned for resale and landowners were advised not to consume certain types.[citation needed] Information regarding physical deformities in the plant and animal populations in the areas affected by radioactive fallout require sampling and capture, along with DNA testing, of individuals to determine if abnormalities are the result of natural mutation, radiation poisoning, or exposure to other contaminants in the environment (i.e. pesticides, industrial waste, or agricultural run-off).
Animals living in contaminated areas in and around Chernobyl have suffered from a variety of side effects caused by radiation. Oxidative stress and low levels of antioxidants have had severe consequences on the development of the nervous system, including reduced brain size and impaired cognitive abilities. It has been found that birds living in areas with high levels of radiation have statistically significantly smaller brains, which has shown to be a deficit to viability in the wild.[16] Barn swallows (Hirundo rustica) that live in or around Chernobyl have displayed an increased rate of physical abnormalities compared to swallows from uncontaminated areas. Abnormalities included partially albinistic plumage, deformed toes, tumors, deformed tail feathers, deformed beaks, and deformed air sacks. Birds with these abnormalities have a reduced viability in the wild and a decrease in fitness. These effects are likely due to radiation exposure and elevated teratogenic effects of radioactive isotopes in the environment.[17]
Invertebrate populations (including bumblebees, butterflies, grasshoppers, dragonflies, and spiders) has significantly decreased. Currently, most radiation around Chernobyl is located in the top layer of soil, where many invertebrates live or lay their eggs. The reduced abundance of invertebrates can have negative implications for the entire ecosystem surrounding Chernobyl.[18]
Radionuclides migrate through either soil diffusion or transportation within the soil solution. The effects of ionizing radiation on plants and trees in particular depends on numerous factors, including climatic conditions, the mechanism of radiation deposition, and the soil type. In turn, radiated vegetation affects organisms further up the food chain. In general, the upper-level trophic organisms received less contamination, due to their ability to be more mobile and feed from multiple areas.[19]
The amount of radioactive nuclides found to have been deposited into surrounding lakes has increased the normal baseline radioactive amounts by 100 percent. Most of the radionuclides in surrounding water areas were found in the sediments at the bottom of the lakes. There has been a high incidence of chromosomal changes in plant and animal aquatic organisms, and this generally has correlated with the contamination and resulting genetic instability. Most of the lakes and rivers surrounding the Chernobyl exclusion zone are still highly contaminated with radionuclides (and will be for many years to come) as the natural decontamination processes of nucleotides with longer half-lives can take many years.[20]
One of the main mechanisms by which radionuclides were passed to humans was through the ingestion of milk from contaminated cows. Most of the rough grazing that the cows took part in contained plant species such as coarse grasses, sedges, rushes, and plants such as heather (also known as calluna vulgaris). These plant species grow in soils that are high in organic matter, low in pH, and are often very well hydrated, thus making the storage and intake of these radionuclides much more feasible and efficient.[21] In the early stages following the Chernobyl accident, high levels of radionuclides were found in the milk and were a direct result of contaminated feeding. Within two months of banning most of the milk that was being produced in the affected areas, officials had phased out the majority of the contaminated feed that was available to the cows and much of the contamination was isolated. In humans, ingestion of milk containing abnormally high levels of iodine radionuclides was the precursor for thyroid disease, especially in children and in the immunocompromised.[21]
Some plants and animals have been able to adapt to the increase radiation levels present in and around Chernobyl. Arabidopsis, a native plant to Chernobyl, are able to resist high concentrations of ionizing radiation and resist forming mutations. This species of plant has been able to develop mechanisms to tolerate chronic radiation that would otherwise be harmful or lethal to other species.[22] Recent studies suggest the 19-mile (30 km) "exclusion zone" surrounding the Chernobyl disaster has become a wildlife sanctuary. Animals have reclaimed the land including rare species such as lynx, Przewalski’s horses, wild boars and eagle owls whose populations are all thriving. When the disaster first occurred, many animals and plants died immediately; however, 25 years later, these animals and plants are reclaiming the abandoned cities to make it their habitat. Even the site of the explosion is flourishing with wildlife as birds nest in the wrecked nuclear plant, and plants and mushrooms live in and on the site.[23]
Due to the bioaccumulation of Caesium-137, some mushrooms as well as wild animals which eat them, e.g. wild boars hunted in Germany and deer in Austria, may have levels which are not considered safe for human consumption.[24] Mandatory radiation testing of sheep in parts of the UK that graze on lands with contaminated peat was lifted in 2012.[25]
Suggested long-range effects[edit]
Graph of Down syndrome cases in Belarus.
Down syndrome (trisomy 21). In West Berlin, Germany, prevalence of Down syndrome (trisomy 21) peaked 9 months following the main fallout.[ 11, 12] Between 1980 and 1986, the birth prevalence of Down syndrome was quite stable (i.e., 1.35–1.59 per 1,000 live births [27–31 cases]). In 1987, 46 cases were diagnosed (prevalence = 2.11 per 1,000 live births). Most of the excess resulted from a cluster of 12 cases among children born in January 1987. The prevalence of Down syndrome in 1988 was 1.77, and in 1989, it reached pre-Chernobyl values. The authors noted that the isolated geographical position of West Berlin prior to reunification, the free genetic counseling, and complete coverage of the population through one central cytogenetic laboratory support completeness of case ascertainment; in addition, constant culture preparation and analysis protocols ensure a high quality of data.[26]
Chromosomal aberrations. Reports of structural chromosome aberrations in people exposed to fallout in Belarus and other parts of the former Soviet Union, Austria, and Germany argue against a simple dose-response relationship between degree of exposure and incidence of aberrations. These findings are relevant because a close relationship exists between chromosome changes and congenital malformations. Inasmuch as some types of aberrations are almost specific for ionizing radiation, researchers use aberrations to assess exposure dose. On the basis of current coefficients, however, one cannot assume that calculation of individual exposure doses resulting from fallout would not induce measurable rates of chromosome aberrations.[citation needed]
Neural tube defects (NTDs) in Turkey. During the embryonic phase of fetal development, the neural tube differentiates into the brain and spinal cord (i.e., collectively forming the central nervous system). Chemical or physical interactions with this process can cause NTDs. Common features of this class of malformations are more or less extended fissures, often accompanied by consecutive dislocation of central nervous system (CNS) tissue. NTDs include spina bifida occulta and aperta, encephalocele, and—in the extreme case—anencephaly. The first evidence in support of a possible association between CNS malformations and fallout from Chernobyl was published by Akar et al.. in 1988. The Mustafakemalpasa State Hospital, Bursa region, covers a population of approximately 90,000. Investigators have documented the prevalence of malformations since 1983. The prevalence of NTDs was 1.7 to 9.2 per 1,000 births, but during the first 6 months of 1987 increased to 20 per 1,000 (12 cases). The excess was most pronounced for the subgroup of anencephalics, in which prevalence increased 5-fold (i.e., 10 per 1,000 [6 cases]). In the consecutive months that followed (i.e., July–December 1987), the prevalence decreased again (1.3 per 1,000 for all NTDs, 0.6 per 1,000 for anencephaly), and it reached pre-Chernobyl levels during the first half of 1988 (all NTDs: 0.6 per 1,000; anencephaly: 0.2 per 1,000). This initial report was supported by several similar findings in observational studies from different regions of Turkey.[citation needed]
Long-term health effects[edit]
Science and politics: the problem of epidemiological studies[edit]
An abandoned village near Pripyat, close to Chernobyl.
The issue of long-term effects of the Chernobyl disaster on civilians is very controversial. The number of people whose lives were affected by the disaster is enormous. Over 300,000 people were resettled because of the disaster; millions lived and continue to live in the contaminated area. On the other hand, most of those affected received relatively low doses of radiation; there is little evidence of increased mortality, cancers or birth defects among them; and when such evidence is present, existence of a causal link to radioactive contamination is uncertain.[27]
An increased incidence of thyroid cancer among children in areas of Belarus, Ukraine and Russia affected by the Chernobyl disaster has been firmly established as a result of screening programs[28] and, in the case of Belarus, an established cancer registry. The findings of most epidemiological studies must be considered interim, say experts, as analysis of the health effects of the disaster is an ongoing process.[29]
Epidemiological studies have been hampered in the Ukraine, Russian Federation and Belarus by a lack of funds, an infrastructure with little or no experience in chronic disease epidemiology, poor communication facilities and an immediate public health problem with many dimensions. Emphasis has been placed on screening rather than on well-designed epidemiological studies. International efforts to organize epidemiological studies have been slowed by some of the same factors, especially the lack of a suitable scientific infrastructure.
Furthermore, the political nature of nuclear energy may have affected scientific studies. In Belarus, Yury Bandazhevsky, a scientist who questioned the official estimates of Chernobyl's consequences and the relevancy of the official maximum limit of 1,000 Bq/kg, was imprisoned from 2001 to 2005. Bandazhevsky and some human rights groups allege his imprisonment was a reprisal for his publication of reports critical of the official research being conducted into the Chernobyl incident.
The activities undertaken by Belarus and Ukraine in response to the disaster — remediation of the environment, evacuation and resettlement, development of uncontaminated food sources and food distribution channels, and public health measures — have overburdened the governments of those countries. International agencies and foreign governments have provided extensive logistic and humanitarian assistance. In addition, the work of the European Commission and World Health Organization in strengthening the epidemiological research infrastructure in Russia, Ukraine and Belarus is laying the basis for major advances in these countries' ability to carry out epidemiological studies of all kinds...
Caesium radioisotopes[edit]
Further information: Fission products
Immediately after the disaster, the main health concern involved radioactive iodine, with a half-life of eight days. Today, there is concern about contamination of the soil with strontium-90 and caesium-137, which have half-lives of about 30 years. The highest levels of caesium-137 are found in the surface layers of the soil where they are absorbed by plants, insects and mushrooms, entering the local food supply. Some scientists fear that radioactivity will affect the local population for the next several generations. Note that caesium is not mobile in most soils because it binds to the clay minerals.[30][31][32]
Tests (ca. 1997) showed that caesium-137 levels in trees of the area were continuing to rise. It is unknown if this is still the case. There is some evidence that contamination is migrating into underground aquifers and closed bodies of water such as lakes and ponds (2001, Germenchuk). The main source of elimination is predicted to be natural decay of caesium-137 to stable barium-137, since runoff by rain and groundwater has been demonstrated to be negligible.
25 years after the catastrophe[edit]
Twenty-five years after the catastrophe, restriction orders remain in place in the production, transportation and consumption of food contaminated by Chernobyl fallout. In the UK, they remain in place on 369 farms covering 750 km² and 200,000 sheep. In parts of Sweden and Finland, restrictions are in place on stock animals, including reindeer, in natural and near-natural environments. "In certain regions of Germany, Austria, Italy, Sweden, Finland, Lithuania and Poland, wild game (including boar and deer), wild mushrooms, berries and carnivorous fish from lakes reach levels of several thousand Bq per kg of caesium-137", while "in Germany, caesium-137 levels in wild boar muscle reached 40,000 Bq/kg. The average level is 6,800 Bq/kg, more than ten times the EU limit of 600 Bq/kg", according to the TORCH 2006 report. The European Commission has stated that "The restrictions on certain foodstuffs from certain Member States must therefore continue to be maintained for many years to come".[8]
As of 2009, sheep farmed in some areas of the UK are still subject to inspection which may lead to them being prohibited from entering the human food chain because of contamination arising from the accident:
"Some of this radioactivity, predominantly radiocaesium-137, was deposited on certain upland areas of the UK, where sheep-farming is the primary land-use. Due to the particular chemical and physical properties of the peaty soil types present in these upland areas, the radiocaesium is still able to pass easily from soil to grass and hence accumulate in sheep. A maximum limit of 1,000 becquerels per kilogramme (Bq/kg) of radiocaesium is applied to sheep meat affected by the accident to protect consumers. This limit was introduced in the UK in 1986, based on advice from the European Commission's Article 31 group of experts. Under power provided under the Food and Environment Protection Act 1985 (FEPA), Emergency Orders have been used since 1986 to impose restrictions on the movement and sale of sheep exceeding the limit in certain parts of Cumbria, North Wales, Scotland and Northern Ireland... When the Emergency Orders were introduced in 1986, the Restricted Areas were large, covering almost 9,000 farms, and over 4 million sheep. Since 1986, the areas covered by restrictions have dramatically decreased and now cover 369 farms, or part farms, and around 200,000 sheep. This represents a reduction of over 95% since 1986, with only limited areas of Cumbria, South Western Scotland and North Wales, covered by restrictions.[33]
369 farms and 190,000 sheep are still affected, a reduction of 95% since 1986, when 9,700 farms and 4,225,000 sheep were under restriction across the United Kingdom.[34]
In Norway, the Sami people were affected by contaminated food (the reindeer had been contaminated by eating lichen, which are accumulate some types of radioactivity).[35]
Effect on the natural world[edit]
Earth Observing-1 image of the reactor and surrounding area in April 2009.
According to reports from Soviet scientists at the First International Conference on the Biological and Radiological Aspects of the Chernobyl Accident (September 1990), fallout levels in the 10 km zone around the plant were as high as 4.81 GBq/m². The so-called "Red Forest" of pine trees,[36][37] previously known as Worm Wood Forest and located immediately behind the reactor complex, lay within the 10 km zone and was killed off by heavy radioactive fallout. The forest is so named because in the days following the disaster the trees appeared to have a deep red hue as they died because of extremely heavy radioactive fallout. In the post-disaster cleanup operations, a majority of the 4 km² forest was bulldozed and buried. The site of the Red Forest remains one of the most contaminated areas in the world.[38]
In recent years there have been many reports suggesting the zone may be a fertile habitat for wildlife.[39] For example in the 1996 BBC Horizon documentary 'Inside Chernobyl's Sarcophagus', birds are seen flying in and out of large holes in the structure itself. Other casual observations suggest biodiversity around the massive radiation spill has increased due to the removal of human influence (see the first hand account of the wildlife preserve). Storks, wolves, beavers, and eagles have been reported in the area.[39]
Barn swallows sampled between 1991 and 2006 both in the Chernobyl exclusion zone had more physical abnormalities than control sparrows sampled elsewhere in Europe. Abnormal barn swallows mated with lower frequency, causing the percentage of abnormal swallows to decrease over time. This demonstrated the selective pressure against the abnormalities was faster than the effects of radiation that created the abnormalities.[40] "This was a big surprise to us," Dr. Mousseau said. "We had no idea of the impact."[39]
It is unknown whether fallout contamination will have any long-term adverse effect on the flora and fauna of the region, as plants and animals have significantly different and varying radiologic tolerance compared with humans. Some birds are reported with stunted tail feathers (which interferes with breeding). There are reports of mutations in plants in the area.[41] The Chernobyl area has not received very much biological study, although studies that have been done suggest that apparently healthy populations may be sink instead of source populations; in other words, that the apparently healthy populations are not contributing to the survival of species.[42]
Using robots, researchers have retrieved samples of highly melanized black fungus from the walls of the reactor core itself. It has been shown that certain species of fungus, such as Cryptococcus neoformans and Cladosporium, can actually thrive in a radioactive environment, growing better than non-melanized variants, implying that they use melanin to harness the energy of ionizing radiation from the reactor.[43][44][45]
Studies on wildlife in the Exclusion Zone[edit]
Main article: Chernobyl Exclusion Zone
The Exclusion Zone around the Chernobyl nuclear power station is reportedly a haven for wildlife.[46][47] As humans were evacuated from the area 25 years ago, existing animal populations multiplied and rare species not seen for centuries have returned or have been reintroduced, for example lynx, wild boar, wolf, Eurasian brown bear, European bison, Przewalski's horse, and eagle owls.[46][47] Birds even nest inside the cracked concrete sarcophagus shielding the shattered remains of Reactor 4.[48] In 2007 the Ukrainian government designated the Exclusion Zone as a wildlife sanctuary,[49][50] and at 488.7 km2 it is one of the largest wildlife sanctuaries in Europe.[47]
According to a 2005 U.N. report, wildlife has returned despite radiation levels that are presently 10 to 100 times higher than normal background radiation. Although radiation levels were significantly higher soon after the accident, they have fallen because of radioactive decay.[48]
Møller and Tim Mousseau have published the results of the largest census of animal life in the Chernobyl Exclusion Zone.[2] It revealed, contrary to the Chernobyl Forum's 2005 report,[3] that the biodiversity of insects, birds and mammals is declining. Not all species are affected by radiation in the same way according to Møller. Some birds—including migrant species and long distance dispersers—are more vulnerable to radiation than others, he said. Martin Hajduch has said that the numbers of animals in the exclusion zone are probably higher now than before the accident because there are no humans there hunting or fishing, "but if you look at how many species of animals are in the area, I think it would be less."[4]
Some researchers have said that by halting the destruction of habitat, the Chernobyl disaster helped wildlife flourish. Biologist Robert J. Baker of Texas Tech University was one of the first to report that Chernobyl had become a wildlife haven and that many rodents he has studied at Chernobyl since the early 1990s have shown remarkable tolerance for elevated radiation levels.[48][50]
Møller et al. (2005) suggested that the reproductive success and annual survival rates of barn swallows are much lower in the Exclusion Zone; 28% of barn swallows inhabiting Chernobyl return each year, while at a control area at Kanev, 250 km to the southeast, the return rate is around 40%.[51][52] A later study by Møller et al. (2007) furthermore claimed an elevated frequency of eleven categories of subtle physical abnormalities in barn swallows, such as bent tail feathers, deformed air sacs, deformed beaks, and isolated albinistic feathers.[53]
Smith et al. (2007) have disputed Møller's findings and instead proposed that a lack of human influence in the Exclusion Zone locally reduced the swallows' insect prey and that radiation levels across the vast majority of the exclusion zone are now too low to have an observable negative effect.[54] But the criticisms raised were responded to in Møller et al. (2008).[55] It is possible that barn swallows are particularly vulnerable to elevated levels of ionizing radiation because they are migratory; they arrive in the exclusion area exhausted and with depleted reserves of radio-protective antioxidants after their journey.[51]
Several research groups have suggested that plants in the area have adapted to cope with the high radiation levels, for example by increasing the activity of DNA cellular repair machinery and by hypermethylation.[56][57][57][58] Given the uncertainties, further research is needed to assess the long-term health effects of elevated ionizing radiation from Chernobyl on flora and fauna.[48]
Chernobyl Forum report and criticisms[edit]
In September 2005, a comprehensive report was published by the Chernobyl Forum, comprising a number of agencies including the International Atomic Energy Agency (IAEA), the World Health Organization (WHO), United Nations bodies and the Governments of Belarus, the Russian Federation and Ukraine. This report titled: "Chernobyl's legacy: Health, Environmental and Socio-Economic Impacts", authored by about 100 recognized experts from many countries, put the total predicted number of deaths due to the disaster around 4,000 (of which 2,200 deaths are expected to be in the ranks of 200,000 liquidators). This predicted death toll includes the 47 workers who died of acute radiation syndrome as a direct result of radiation from the disaster, nine children who died from thyroid cancer and an estimated 4000 people who could die from cancer as a result of exposure to radiation. This number was subsequently updated to 9000 excess cancer deaths.[59]
An IAEA press officer admitted that the 4000 figure was given prominence in the report "...to counter the much higher estimates which had previously been seen. ... "It was a bold action to put out a new figure that was much less than conventional wisdom.""[60]
The report also stated that, apart from a 30 kilometre area around the site and a few restricted lakes and forests, radiation levels had returned to acceptable levels.[61] For full coverage see the IAEA Focus Page.[62]
The methodology of the Chernobyl Forum report has been disputed by some advocacy organizations opposed to nuclear energy, such as Greenpeace and the International Physicians for Prevention of Nuclear Warfare (IPPNW), as well as some individuals such as Elisabeth Cardis of the International Agency for Research on Cancer,[63] Dr. Michel Fernex, retired medical doctor from the WHO and campaigner Dr. Christopher Busby (Green Audit, LLRC). The main criticism has been with regard to the restriction of the Forum's study to Belarus, Ukraine and Russia. Furthermore, it only studied the case of 200,000 people involved in the cleanup, and the 400,000 most directly affected by the released radiation. German Green Party Member of the European Parliament Rebecca Harms, commissioned a report on Chernobyl in 2006 (TORCH, The Other Report on Chernobyl). The 2006 TORCH report claimed that:
"In terms of their surface areas, Belarus (22% of its land area) and Austria (13%) were most affected by higher levels of contamination. Other countries were seriously affected; for example, more than 5% of Ukraine, Finland and Sweden were contaminated to high levels (> 40,000 Bq/m² caesium-137). More than 80% of Moldova, the European part of Turkey, Slovenia, Switzerland, Austria and the Slovak Republic were contaminated to lower levels (> 4,000 Bq/m² caesium-137). And 44% of Germany and 34% of the UK were similarly affected." (See map of radioactive distribution of Caesium-137 in Europe)[8]
While the IAEA/WHO and UNSCEAR considered areas with exposure greater than 40,000 Bq/m², the TORCH report also included areas contaminated with more than 4,000 Bq/m² of Cs-137.
The TORCH 2006 report "estimated that more than half the iodine-131 from Chernobyl [which increases the risk of thyroid cancer] was deposited outside the former Soviet Union. Possible increases in thyroid cancer have been reported in the Czech Republic and the UK, but more research is needed to evaluate thyroid cancer incidences in Western Europe". It predicted about 30,000 to 60,000 excess cancer deaths, 7 to 15 Times greater than the figure of 4,000 in the IAEA press release; warned that predictions of excess cancer deaths strongly depend on the risk factor used; and predicted excess cases of thyroid cancer range between 18,000 and 66,000 in Belarus alone depending on the risk projection model.[64] However, elevated incidence thyroid cancer is still seen among Ukrainians who were exposed to radioactivity due to Chernobyl accident during their childhood, but who were diagnosed the malignancy as adults.[65]
Another study claims possible heightened mortality in Sweden.[66]
Greenpeace quoted a 1998 WHO study, which counted 212 dead from only 72,000 liquidators. The environmental NGO estimated a total death toll of 93,000 but cite in their report that “The most recently published figures indicate that in Belarus, Russia and the Ukraine alone the disaster could have resulted in an estimated 200,000 additional deaths in the period between 1990 and 2004.” In its report, Greenpeace suggested there will be 270,000 cases of cancer alone attributable to Chernobyl fallout, and that 93,000 of these will probably be fatal compare with the IAEA 2005 report which claimed that "99% of thyroid cancers wouldn't be lethal".[67]
Blake Lee-Harwood, campaigns director at Greenpeace, declared that cancer was likely to be the cause of less than half of the final fatalities; "intestinal problems, heart and circulation problems, respiratory problems, endocrine problems, and particularly effects on the immune system," are also concerns. Lee-Harwood alleged that the nuclear industry had a "vested interest in playing down Chernobyl because it's an embarrassment to them". Responding to these criticisms, the WHO spokesman Gregory Hartl explained that "the Greenpeace report is looking at all of Europe, whereas our report looks at only the most affected areas of the three most affected countries,".[67]
According to the Union Chernobyl, the main organization of liquidators, 10% of the 600,000 liquidators are now dead, and 165,000 disabled.[68]
According to an April 2006 report by the International Physicians for Prevention of Nuclear Warfare (IPPNW), entitled "Health Effects of Chernobyl - 20 years after the reactor catastrophe",[69] more than 10,000 people are today affected by thyroid cancer and 50,000 cases are expected. In Europe, the IPPNW claims that 10,000 deformities have been observed in newborns because of Chernobyl's radioactive discharge, with 5,000 deaths among newborn children. They also state that several hundreds of thousands of the people who worked on the site after the disaster are now sick because of radiation, and tens of thousands are dead.[68]
Revisiting the issue for the 25th anniversary of the Chernobyl disaster, the Union of Concerned Scientists described the Forum's estimate of four thousand as pertaining only to "a much smaller subgroup of people who experienced the greatest exposure to released radiation". Their estimates for the broader population are 50,000 excess cancer cases resulting in 25,000 excess cancer deaths.[70]
Controversy over human health effects[edit]
The majority of premature deaths caused by Chernobyl are expected to be the result of cancers and other diseases induced by radiation in the decades after the event. This will be the result of a large population (some studies have considered the entire population of Europe) exposed to relatively low doses of radiation increasing the risk of cancer across that population. Interpretations of the current health state of exposed populations vary. Therefore, estimates of the ultimate human impact of the disaster have relied on numerical models of the effects of radiation on health. Furthermore, the effects of low-level radiation on human health are not well understood, and so the models used, notably the linear no threshold model, are open to question.
Given these factors, studies of Chernobyl's health effects have come up with different conclusions and are the subject of scientific and political controversy. The following section presents some of the major studies on this topic.
Chernobyl Forum report[edit]
In September 2005, a draft summary report by the Chernobyl Forum, comprising a number of UN agencies including the International Atomic Energy Agency (IAEA), the World Health Organization (WHO), the United Nations Development Programme (UNDP), other UN bodies and the Governments of Belarus, the Russian Federation and Ukraine, put the total predicted number of deaths due to the accident at 4000.[62] This death toll predicted by the WHO included the 47 workers who died of acute radiation syndrome as a direct result of radiation from the disaster and nine children who died from thyroid cancer, in the estimated 4000 excess cancer deaths expected among the 600,000 with the highest levels of exposure.[71]
The full version of the WHO health effects report adopted by the UN, published in April 2006, included the prediction of 5000 additional fatalities from significantly contaminated areas in Belarus, Russia and Ukraine and predicted that, in total, 9000 will die from cancer among the 6.9 million most-exposed Soviet citizens.[63][not in citation given]This report is not free of controversy, and has been accused of trying to minimize the consequences of the accident.[72]
TORCH report[edit]
Main article: TORCH report
In 2006 German Green Party Member of the European Parliament Rebecca Harms commissioned two UK scientists for an alternate report (TORCH, The Other Report on CHernobyl) in response to the UN report. The report included areas not covered by the Chernobyl forum report, and also lower radiation doses. It predicted about 30,000 to 60,000 excess cancer deaths and warned that predictions of excess cancer deaths strongly depend on the risk factor used, and urged more research stating that large uncertainties made it difficult to properly assess the full scale of the disaster.[8]
Greenpeace[edit]
Demonstration on Chernobyl day near WHO in Geneva
Greenpeace claimed contradictions in the Chernobyl Forum reports, quoting a 1998 WHO study referenced in the 2005 report, which projected 212 dead from 72,000 liquidators.[73] In its report, Greenpeace suggested there will be 270,000 cases of cancer attributable to Chernobyl fallout, and that 93,000 of these will probably be fatal, but state in their report that "The most recently published figures indicate that in Belarus, Russia and Ukraine alone the accident could have resulted in an estimated 200,000 additional deaths in the period between 1990 and 2004." Blake Lee-Harwood, campaigns director at Greenpeace, believes that cancer was likely to be the cause of less than half of the final fatalities and that "intestinal problems, heart and circulation problems, respiratory problems, endocrine problems, and particularly effects on the immune system," will also cause fatalities. However, concern has been expressed about the methods used in compiling the Greenpeace report.[72][74] It is not peer reviewed nor does it rely on peer review science as the Chernobyl Forum report did.
April 2006 IPPNW report[edit]
According to an April 2006 report by the German affiliate of the International Physicians for Prevention of Nuclear Warfare (IPPNW), entitled "Health Effects of Chernobyl", more than 10,000 people are today affected by thyroid cancer and 50,000 cases are expected. The report projected tens of thousands dead among the liquidators. In Europe, it alleges that 10,000 deformities have been observed in newborns because of Chernobyl's radioactive discharge, with 5000 deaths among newborn children. They also claimed that several hundreds of thousands of the people who worked on the site after the accident are now sick because of radiation, and tens of thousands are dead.[75]
New York Academy of Sciences publication[edit]
Chernobyl: Consequences of the Catastrophe for People and the Environment is an English translation of the 2007 Russian publication Chernobyl. It was published online in 2009 by the New York Academy of Sciences in their Annals of the New York Academy of Sciences. It presents an analysis of scientific literature and concludes that medical records between 1986, the year of the accident, and 2004 reflect 985,000 deaths as a result of the radioactivity released. The authors suggest that most of the deaths were in Russia, Belarus and Ukraine, but others were spread through the many other countries the radiation from Chernobyl struck.[76]
The literature analysis draws on over 1,000 published titles and over 5,000 internet and printed publications discussing the consequences of the Chernobyl disaster. The authors contend that those publications and papers were written by leading Eastern European authorities and have largely been downplayed or ignored by the IAEA and UNSCEAR.[77] Author Alexy V. Yablokov was also one of the general editors on the Greenpeace commissioned report also criticizing the Chernobyl Forum finds published one year prior to the Russian language version of this report.
A critical review by Dr. Monty Charles in the journal Radiation Protection Dosimetry states that Consequences is a direct extension of the 2005 Greenpeace report, updated with data of unknown quality.[78] The New York Academy of Sciences also published a severely critical review by M. I. Balonov from the Institute of Radiation Hygiene (St. Petersburg, Russia) which stated that "The value of [Consequences] is not zero, but negative, as its bias is obvious only to specialists, while inexperienced readers may well be put into deep error."[79]
2011 UNSCEAR report[edit]
The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) produced a report [80] drastically different to many appreciations of the effects previously produced. The report concludes that 134 staff and emergency workers suffered acute radiation syndrome and of those 28 died of the condition. Many of the survivors suffered skin conditions and radiation induced cataracts, and 19 have since died, but not usually of conditions associated with radiation exposure. Of the several hundred thousand liquidators, apart from indications of increased leukaemia risk, there is no other evidence of health effects. In the general public, the only effect with 'persuasive evidence' is a substantial fraction of the 6,000 cases of thyroid cancer in adolescents observed in the affected areas. By 2005, 15 cases had proved fatal.
The total deaths reliably attributable to the radiation produced by the accident therefore stands at 62 by the estimate of UNSCEAR.
The report concludes that 'the vast majority of the population need not live in fear of serious health consequences from the Chernobyl accident'.
Other studies and claims[edit]
The Ukrainian Health Minister claimed in 2006 that more than 2.4 million Ukrainians, including 428,000 children, suffer from health problems related to the catastrophe.[6] Psychological after-effects, as the 2006 UN report pointed out, have also had adverse effects on internally displaced persons.
In a recently published study scientists from Forschungszentrum Jülich, Germany, published the “Korma-Report” with data of radiological long-term measurements that were performed between 1998 and 2007 in a region in Belarus that was affected by the Chernobyl accident. The internal radiation exposure of the inhabitants in a village in Korma County/Belarus caused by the existing radioactive contamination has experienced a significant decrease from a very high level. The external exposure, however, reveals a different picture. Although an overall decrease was observed, the organic constituents of the soil show an increase in contamination. This increase was not observed in soils from cultivated land or gardens. According to the Korma Report the internal dose will decrease to less than 0.2 mSv/a in 2011 and to below 0.1 mSv/a in 2020. Despite this, the cumulative dose will remain significantly higher than “normal” values due to external exposure. Resettlement may even be possible in former prohibited areas provided that people comply with appropriate dietary rules.[81]
Study of heightened mortality in Sweden.[66][82] But it must be pointed out that this study, and in particular the conclusions drawn has been very criticized [83] (article in Swedish from the Swedish doctors magazine)
One study reports increased levels of birth defects in Germany and Finland in the wake of the accident.[84]
A change in the human sex ratio at birth in several European countries has been linked to Chernobyl fallout.[85][86]
In the Czech Republic, thyroid cancer has increased significantly after Chernobyl.[87]
A report from the European Committee on Radiation Risk (a body sponsored by the European Green Party) claims that the World Health Organization, together with most other international and national health bodies, has marginalized or ignored, perhaps purposely, the terrible consequences of the Chernobyl fallout to protect the vested interests of the nuclear industry.[88]
The Abstract of the April 2006 International Agency for Research on Cancer report Estimates of the cancer burden in Europe from radioactive fallout from the Chernobyl accident stated "It is unlikely that the cancer burden from the largest radiological accident to date could be detected by monitoring national cancer statistics. Indeed, results of analyses of time trends in cancer incidence and mortality in Europe do not, at present, indicate any increase in cancer rates – other than of thyroid cancer in the most contaminated regions – that can be clearly attributed to radiation from the Chernobyl accident."[89][90] They estimate, based on the linear no threshold model of cancer effects, that 16,000 excess cancer deaths could be expected from the effects of the Chernobyl accident up to 2065. Their estimates have very wide 95% confidence intervals from 6,700 deaths to 38,000.[91]
The application of the linear no threshold model to predict deaths from low levels of exposure to radiation was disputed in a BBC (British Broadcasting Corporation) Horizon documentary, broadcast on 13 July 2006.[92] It offered statistical evidence to suggest that there is an exposure threshold of about 200 millisieverts, below which there is no increase in radiation-induced disease. Indeed it went further, reporting research from Professor Ron Chesser of Texas Tech University, which suggests that low exposures to radiation can have a protective effect. The program interviewed scientists who believe that the increase in thyroid cancer in the immediate area of the explosion had been over-recorded, and predicted that the estimates for widespread deaths in the long term would be proved wrong. It noted the view of the World Health Organization scientist Dr Mike Rapacholi that, while most cancers can take decades to manifest, leukemia manifests within a decade or so: none of the previously expected peak of leukemia deaths has been found, and none is now expected. Identifying the need to balance the "fear response" in the public's reaction to radiation, the program quoted Dr Peter Boyle, director of the IARC: "Tobacco smoking will cause several thousand times more cancers in the [European] population."[93]
Professor Wade Allison of Oxford University (a lecturer in medical physics and particle physics) gave a talk on ionising radiation 24 November 2006 in which he gave an approximate figure of 81 cancer deaths from Chernobyl (excluding 28 cases from acute radiation exposure and the thyroid cancer deaths which he regards as "avoidable"). In a closely reasoned argument using statistics from therapeutic radiation, exposure to elevated natural radiation (the presence of radon gas in homes) and the diseases of Hiroshima and Nagasaki survivors he demonstrated that the linear no-threshold model should not be applied to low-level exposure in humans, as it ignores the well-known natural repair mechanisms of the body.[94][95]
A photographic essay by photojournalist Paul Fusco documents the legacy of the meltdown on local children [96][97]
Bandashevsky measured levels of radioisotopes in children who had died in the Minsk area that had received Chernobyl fallout, and the cardiac findings were the same as those seen in test animals that had been administered Cs-137.[98]
French legal action[edit]
Since March 2001, 400 lawsuits have been filed in France against "X" (the French equivalent of John Doe, an unknown person or company) by the French Association of Thyroid-affected People, including 200 in April 2006. These persons are affected by thyroid cancer or goitres, and have filed lawsuits alleging that the French government, at the time led by Prime Minister Jacques Chirac, had not adequately informed the population of the risks linked to the Chernobyl radioactive fallout. The complaint contrasts the health protection measures put in place in nearby countries (warning against consumption of green vegetables or milk by children and pregnant women) with the relatively high contamination suffered by the east of France and Corsica. Although the 2006 study by the French Institute of Radioprotection and Nuclear Safety said that no clear link could be found between Chernobyl and the increase of thyroid cancers in France, it also stated that papillary thyroid cancer had tripled in the following years.[99]
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