Chernobyl disaster effects
Encyclopedia
The Chernobyl disaster
Chernobyl disaster
The Chernobyl disaster was a nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in Ukraine , which was under the direct jurisdiction of the central authorities in Moscow...

 triggered the release of substantial amounts of radiation
Ionizing radiation
Ionizing radiation is radiation composed of particles that individually have sufficient energy to remove an electron from an atom or molecule. This ionization produces free radicals, which are atoms or molecules containing unpaired electrons...

 into the atmosphere in the form of both particulate and gaseous radioisotopes
Radionuclide
A radionuclide is an atom with an unstable nucleus, which is a nucleus characterized by excess energy available to be imparted either to a newly created radiation particle within the nucleus or to an atomic electron. The radionuclide, in this process, undergoes radioactive decay, and emits gamma...

. It is the most significant unintentional release of radiation
Radiation
In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...

 into the environment
Natural environment
The natural environment encompasses all living and non-living things occurring naturally on Earth or some region thereof. It is an environment that encompasses the interaction of all living species....

 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
Atomic bombings of Hiroshima and Nagasaki
During the final stages of World War II in 1945, the United States conducted two atomic bombings against the cities of Hiroshima and Nagasaki in Japan, the first on August 6, 1945, and the second on August 9, 1945. These two events are the only use of nuclear weapons in war to date.For six months...

 in 1945. However, the work of the Scientific Committee on Problems of the Environment
Scientific Committee on Problems of the Environment
The Scientific Committee on Problems of the Environment was established by the 10th meeting of the Executive Committee of the ICSU in 1969. SCOPE's members include 38 national science academies and research councils, and 22 international scientific unions.The current president is Lu Yonglong...

 (SCOPE) suggests that the two events cannot be directly compared, with a number suggesting that one was x times larger than the other; the isotopes released at Chernobyl tended to be longer-lived than those released by a bomb detonation, producing radioactivity curves that vary in shape as well as size.

Dose to the general public within 30 km of the plant

The inhalation dose (internal dose) for the public (during the time between the accident occurring 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
Caesium-137
Caesium-137 is a radioactive isotope of caesium which is formed as a fission product by nuclear fission.It has a half-life of about 30.17 years, and decays by beta emission to a metastable nuclear isomer of barium-137: barium-137m . Caesium-137 is a radioactive isotope of caesium which is formed...

) to be between 3 and 150 mSv {between a 1 in 6700 and a 1 in 130 chance of a fatal cancer, assuming the ICRP risk factor of a 5% of a fatal cancer per Sv
Sievert
The sievert is the International System of Units SI derived unit of dose equivalent radiation. It attempts to quantitatively evaluate the biological effects of ionizing radiation as opposed to just the absorbed dose of radiation energy, which is measured in gray...

 of exposure} for adults (depending on the distance from the reactor and the day of evacuation) and for one year old children a dose estimate of between 10 and 700 mSv {between a 1 in 2000 and a 1 in 30 chance of fatal cancer} has been made. Thyroid doses for adults were between 20 and 1000 mSv, while for the one year old infants these were higher at 20 to 6000 mSv. For those who left at an early stage in 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 (circa 40%), tellurium and rubidium
Rubidium
Rubidium is a chemical element with the symbol Rb and atomic number 37. Rubidium is a soft, silvery-white metallic element of the alkali metal group. Its atomic mass is 85.4678. Elemental rubidium is highly reactive, with properties similar to those of other elements in group 1, such as very rapid...

 isotopes (circa 20 to 30% for Rb and Te).

The ingestion doses in this same group of people have also been estimated using the caesium 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/animals to humans. For adults the dose has been estimated to be between 3 and 180 mSv while for the one year old infants a dose of between 20 and 1300 mSv has been estimated. Again the majority of the dose was due to Iodine-131 and the external dose was much smaller than the internal dose due to the radioactivity in the diet.

Short-term health effects and immediate results

The explosion at the power station and subsequent fires inside the remains of the reactor provoked a radioactive cloud which drifted not only over Russia, Belarus
Belarus
Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,...

 and Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

, but also over the European part of Turkey
Turkey
Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...

, Greece, Moldova
Moldova
Moldova , officially the Republic of Moldova is a landlocked state in Eastern Europe, located between Romania to the West and Ukraine to the North, East and South. It declared itself an independent state with the same boundaries as the preceding Moldavian Soviet Socialist Republic in 1991, as part...

, Romania
Romania
Romania is a country located at the crossroads of Central and Southeastern Europe, on the Lower Danube, within and outside the Carpathian arch, bordering on the Black Sea...

, Bulgaria
Bulgaria
Bulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east...

, Lithuania
Lithuania
Lithuania , officially the Republic of Lithuania is a country in Northern Europe, the biggest of the three Baltic states. It is situated along the southeastern shore of the Baltic Sea, whereby to the west lie Sweden and Denmark...

, Finland, Denmark, Norway, Sweden, Austria, Hungary
Hungary
Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...

, Czechoslovakia
Czechoslovakia
Czechoslovakia or Czecho-Slovakia was a sovereign state in Central Europe which existed from October 1918, when it declared its independence from the Austro-Hungarian Empire, until 1992...

, Yugoslavia
Yugoslavia
Yugoslavia refers to three political entities that existed successively on the western part of the Balkans during most of the 20th century....

, Poland, Estonia, Switzerland, Germany, Italy, Ireland, France (including Corsica
Corsica
Corsica is an island in the Mediterranean Sea. It is located west of Italy, southeast of the French mainland, and north of the island of Sardinia....

), Canada and the United Kingdom (UK). 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 April 27 workers at the Forsmark Nuclear Power Plant
Forsmark Nuclear Power Plant
Forsmark Nuclear Power Plant is a nuclear power plant in Forsmark, Sweden, and also the site of the Swedish Final repository for radioactive operational waste...

 (approximately 1100 km from the Chernobyl site) were found to have radioactive particles on their clothes. 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 (mushroom
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...

s 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
Belarus
Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,...

 received about 60% of the contamination that fell on the former Soviet Union. A large area in Russia south of Bryansk
Bryansk
Bryansk is a city and the administrative center of Bryansk Oblast, Russia, located southwest of Moscow. Population: -History:The first written mention of Bryansk was in 1146, in the Hypatian Codex, as Debryansk...

 was also contaminated, as were parts of northwestern Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

.

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
Radiation
In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...

 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
Becquerel
The becquerel is the SI-derived unit of radioactivity. One Bq is defined as the activity of a quantity of radioactive material in which one nucleus decays per second. The Bq unit is therefore equivalent to an inverse second, s−1...

 (depending on source) of radioactive contamination
Radioactive contamination
Radioactive contamination, also called radiological contamination, is radioactive substances on surfaces, or within solids, liquids or gases , where their presence is unintended or undesirable, or the process giving rise to their presence in such places...

 released from the reactor. An additional 10 individuals have already died of cancer as a result of the disaster.

Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 scientists reported that the Chernobyl Unit 4 reactor contained about 180–190 metric tons of uranium dioxide
Uranium dioxide
Uranium dioxide or uranium oxide , also known as urania or uranous oxide, is an oxide of uranium, and is a black, radioactive, crystalline powder that naturally occurs in the mineral uraninite. It is used in nuclear fuel rods in nuclear reactors. A mixture of uranium and plutonium dioxides is used...

 fuel and fission products. Estimates of the amount of this material that escaped range from 5 to 30 percent, but some liquidator
Liquidator (Chernobyl)
Liquidators , or "clean-up workers", is the name given in the former USSR to people who were called upon to work in efforts to deal with consequences of the April 26, 1986, Chernobyl disaster on the site of the event...

s, 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 completely empty. Because of the intense heat of the fire, much of the ejected fuel was lofted high into the atmosphere (with no containment building
Containment building
A containment building, in its most common usage, is a steel or reinforced concrete structure enclosing a nuclear reactor. It is designed, in any emergency, to contain the escape of radiation to a maximum pressure in the range of 60 to 200 psi...

 to stop it), where it spread.

Workers and liquidators

The workers involved in the recovery and cleanup after the disaster, called "liquidators
Liquidator (Chernobyl)
Liquidators , or "clean-up workers", is the name given in the former USSR to people who were called upon to work in efforts to deal with consequences of the April 26, 1986, Chernobyl disaster on the site of the event...

", received high doses of radiation. In most cases, these workers were not equipped with individual dosimeter
Dosimeter
Dosimeters measure an individual's or an object'sexposure to something in the environment — particularly to a hazard inflicting cumulative impact over long periods of time, or over a lifetime...

s 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. According to Soviet estimates, between 300,000 and 600,000 people were involved in the cleanup of the 30 km evacuation zone
Zone of alienation
The Chernobyl Nuclear Power Plant Zone, which is sometimes referred to as The Chernobyl Zone, The 30 Kilometer Zone, The Zone of Alienation, or simply The Zone The Chernobyl Nuclear Power Plant Zone, which is sometimes referred to as The Chernobyl Zone, The 30 Kilometer Zone, The Zone of...

 around the reactor, but many of them entered the zone two years after the disaster. Estimates of the number of "liquidators" vary; the World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...

, for example, puts the figure at about 800,000; Russia lists as liquidators some people who did not work in contaminated areas. In the first year after the disaster, the number of cleanup workers in the zone was estimated to be 211,000, and these workers received an estimated average dose of 165 millisieverts
Sievert
The sievert is the International System of Units SI derived unit of dose equivalent radiation. It attempts to quantitatively evaluate the biological effects of ionizing radiation as opposed to just the absorbed dose of radiation energy, which is measured in gray...

 (16.5 rem).
The plume of radioactive debris has been said to be equal to the contamination of 400 Hiroshima bombs
Atomic bombings of Hiroshima and Nagasaki
During the final stages of World War II in 1945, the United States conducted two atomic bombings against the cities of Hiroshima and Nagasaki in Japan, the first on August 6, 1945, and the second on August 9, 1945. These two events are the only use of nuclear weapons in war to date.For six months...

. This is correct, but misleading. The main effect of the bomb was the direct radiation from the gamma blast. Compared to that, the contamination was only a minor addition. Furthermore the comparison to bomb fallout is very misleading, as an atomic bomb has a very different isotope signature to a power reactor. In bomb fallout plenty of the very short-lived isotopes are present while the activity in used power reactor fuel tends have a medium to long half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...

. The time required for the dose rate to decline by a factor of 10 in an area covered with fallout from an atomic bomb which has detonated an hour ago is much shorter than the time required for the same reduction in dose rate due to Chernobyl fallout (one hour after the reactor suffered the steam explosion). A sevenfold increase in DNA mutations has been identified in liquidators' children conceived after the accident, when compared to their siblings conceived before. However, the effect diminishes sharply with time.

Evacuation

Soviet authorities started evacuating people from the area around Chernobyl only on the second day after the disaster (after 36 hours).
By May 1986, about a month later, all those living within a 30 km (18.6 mi) radius of the plant — about 116,000 people — had been relocated. This area is often referred to as the zone of alienation
Zone of alienation
The Chernobyl Nuclear Power Plant Zone, which is sometimes referred to as The Chernobyl Zone, The 30 Kilometer Zone, The Zone of Alienation, or simply The Zone The Chernobyl Nuclear Power Plant Zone, which is sometimes referred to as The Chernobyl Zone, The 30 Kilometer Zone, The Zone of...

. However, radiation affected the area in a much wider scale than this 30 km radius.

According to reports from Soviet scientists, 28,000 km² (10,800 mi²) were contaminated by cesium-137 to levels greater than 185 kBq/m². 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.

Civilians

Some children in the contaminated areas were exposed to high radiation doses of up to 50 grays
Gray (unit)
The gray is the SI unit of absorbed radiation dose of ionizing radiation , and is defined as the absorption of one joule of ionizing radiation by one kilogram of matter ....

 (Gy) because of an intake of radioactive iodine-131
Iodine-131
Iodine-131 , also called radioiodine , is an important radioisotope of iodine. It has a radioactive decay half-life of about eight days. Its uses are mostly medical and pharmaceutical...

, a relatively short-lived isotope with a half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...

 of 8 days, from contaminated milk produced locally. Several studies have found that the incidence of thyroid cancer
Thyroid cancer
Thyroid neoplasm is a neoplasm or tumor of the thyroid. It can be a benign tumor such as thyroid adenoma, or it can be a malignant neoplasm , such as papillary, follicular, medullary or anaplastic thyroid cancer. Most patients are 25 to 65 years of age when first diagnosed; women are more affected...

 among children in Belarus, Ukraine and Russia has risen sharply. The 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 as far higher than normal", but 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
Iodine-131
Iodine-131 , also called radioiodine , is an important radioisotope of iodine. It has a radioactive decay half-life of about eight days. Its uses are mostly medical and pharmaceutical...

 therapy for any metastases. To date, such treatment appears to have been successful in the vast majority of cases.

Late in 1995, the World Health Organisation (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. 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. Presumably either the increase is unrelated to the disaster or the mechanisms behind it are not well understood.

Plant and animal health

A large swath of pine forest killed by acute radiation was named the Red Forest
Red Forest
The Red Forest , formerly the Worm Wood Forest, refers to the trees in the 10 km² surrounding the Chernobyl Nuclear Power Plant. The name 'Red Forest' comes from the ginger-brown colour of the pine trees after they died following the absorption of high levels of radiation from the Chernobyl...

. The dead pines were bulldozed and buried. Livestock were removed during the human evacuations. 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. Information regarding physical deformities in the plant and animal populations in the areas affected by radioactive fallout require capture and DNA testing of individuals to determine if abnormalities are the result of natural mutation, radiation poisoning, or exposure to other contaminants in the environment such as pesticides, industrial waste, or agricultural run-off.

Suggested long-range effects

  • Down syndrome
    Down syndrome
    Down syndrome, or Down's syndrome, trisomy 21, is a chromosomal condition caused by the presence of all or part of an extra 21st chromosome. It is named after John Langdon Down, the British physician who described the syndrome in 1866. The condition was clinically described earlier in the 19th...

     (trisomy 21). In West Berlin
    West Berlin
    West Berlin was a political exclave that existed between 1949 and 1990. It comprised the western regions of Berlin, which were bordered by East Berlin and parts of East Germany. West Berlin consisted of the American, British, and French occupation sectors, which had been established in 1945...

    , Germany
    Germany
    Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

    , 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
    Cluster (epidemiology)
    A cluster refers to a grouping of health-related events that are related temporally and in proximity. Typically, when clusters are recognized, they are reported to public health departments in the local area. The 1854 cholera outbreak which occurred in London is a classical example of 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
    Genetic counseling
    Genetic counseling or traveling is the process by which patients or relatives, at risk of an inherited disorder, are advised of the consequences and nature of the disorder, the probability of developing or transmitting it, and the options open to them in management and family planning...

    , 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.
  • 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
    Ionizing radiation
    Ionizing radiation is radiation composed of particles that individually have sufficient energy to remove an electron from an atom or molecule. This ionization produces free radicals, which are atoms or molecules containing unpaired electrons...

    , 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.
  • Neural tube defects (NTDs) in Turkey
    Turkey
    Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...

    . During the embryo
    Embryo
    An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of first cell division until birth, hatching, or germination...

    nic phase of fetal development
    Fetal development
    Prenatal or antenatal development is the process in which a human embryo or fetus gestates during pregnancy, from fertilization until birth. Often, the terms fetal development, foetal development, or embryology are used in a similar sense.After fertilization the embryogenesis starts...

    , the neural tube
    Neural tube
    In the developing vertebrate, the neural tube is the embryo's precursor to the central nervous system, which comprises the brain and spinal cord...

     differentiates
    Cellular differentiation
    In developmental biology, cellular differentiation is the process by which a less specialized cell becomes a more specialized cell type. Differentiation occurs numerous times during the development of a multicellular organism as the organism changes from a simple zygote to a complex system of...

     into the brain
    Brain
    The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...

     and spinal cord
    Spinal cord
    The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain . The brain and spinal cord together make up the central nervous system...

     (i.e., collectively forming the central nervous system
    Central nervous system
    The central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish...

    ). Chemical or physical interactions with this process can cause NTDs. Common features of this class of malformations are more or less extended fissure
    Fissure
    In anatomy, a fissure is a groove, natural division, deep furrow, elongated cleft, or tear in various parts of the body.-Brain:...

    s, often accompanied by consecutive dislocation of central nervous system (CNS) tissue. NTDs include spina bifida
    Spina bifida
    Spina bifida is a developmental congenital disorder caused by the incomplete closing of the embryonic neural tube. Some vertebrae overlying the spinal cord are not fully formed and remain unfused and open. If the opening is large enough, this allows a portion of the spinal cord to protrude through...

     occulta and aperta, encephalocele
    Encephalocele
    Encephalocele, sometimes known by the Latin name cranium bifidum, is a neural tube defect characterized by sac-like protrusions of the brain and the membranes that cover it through openings in the skull. These defects are caused by failure of the neural tube to close completely during fetal...

    , and—in the extreme case—anencephaly
    Anencephaly
    Anencephaly is a cephalic disorder that results from a neural tube defect that occurs when the cephalic end of the neural tube fails to close, usually between the 23rd and 26th day of pregnancy, resulting in the absence of a major portion of the brain, skull, and scalp...

    . 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
    Prevalence
    In epidemiology, the prevalence of a health-related state in a statistical population is defined as the total number of cases of the risk factor in the population at a given time, or the total number of cases in the population, divided by the number of individuals in the population...

     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.

Science and politics: the problem of epidemiological studies

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.

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 and, in the case of Belarus, an established cancer registry
Cancer registry
A cancer registry is a systematic collection of data about cancer and tumor diseases. The data is collected by Cancer Registrars. Cancer Registrars capture a complete summary of patient history, diagnosis, treatment, and status for every cancer patient in the United States, and other countries as...

. 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.

Epidemiological studies have been hampered in the former Soviet Union by a lack of funds, an infrastructure with little or no experience in chronic disease epidemiology
Epidemiology
Epidemiology is the study of health-event, health-characteristic, or health-determinant patterns in a population. It is the cornerstone method of public health research, and helps inform policy decisions and evidence-based medicine by identifying risk factors for disease and targets for preventive...

, 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
Nuclear power
Nuclear power is the use of sustained nuclear fission to generate heat and electricity. Nuclear power plants provide about 6% of the world's energy and 13–14% of the world's electricity, with the U.S., France, and Japan together accounting for about 50% of nuclear generated electricity...

 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
European Commission
The European Commission is the executive body of the European Union. The body is responsible for proposing legislation, implementing decisions, upholding the Union's treaties and the general day-to-day running of the Union....

 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

Immediately after the disaster, the main health concern involved radioactive iodine, with a half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...

 of eight days. Today, there is concern about contamination of the soil with strontium-90
Strontium-90
Strontium-90 is a radioactive isotope of strontium, with a half-life of 28.8 years.-Radioactivity:Natural strontium is nonradioactive and nontoxic, but 90Sr is a radioactivity hazard...

 and caesium-137
Caesium-137
Caesium-137 is a radioactive isotope of caesium which is formed as a fission product by nuclear fission.It has a half-life of about 30.17 years, and decays by beta emission to a metastable nuclear isomer of barium-137: barium-137m . Caesium-137 is a radioactive isotope of caesium which is formed...

, 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. Tests (ca. 1997) have shown that caesium-137 levels in trees of the area are continuing to rise. There is some evidence that contamination is migrating into underground aquifer
Aquifer
An aquifer is a wet underground layer of water-bearing permeable rock or unconsolidated materials from which groundwater can be usefully extracted using a water well. The study of water flow in aquifers and the characterization of aquifers is called hydrogeology...

s 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
Barium
Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Barium is never found in nature in its pure form due to its reactivity with air. Its oxide is historically known as baryta but it reacts with...

-137, since runoff by rain and groundwater has been demonstrated to be negligible.

25 years after the catastrophe

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".

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
Food chain
A food web depicts feeding connections in an ecological community. Ecologists can broadly lump all life forms into one of two categories called trophic levels: 1) the autotrophs, and 2) the heterotrophs...

 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 becquerel
Becquerel
The becquerel is the SI-derived unit of radioactivity. One Bq is defined as the activity of a quantity of radioactive material in which one nucleus decays per second. The Bq unit is therefore equivalent to an inverse second, s−1...

s 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
Cumbria
Cumbria , is a non-metropolitan county in North West England. The county and Cumbria County Council, its local authority, came into existence in 1974 after the passage of the Local Government Act 1972. Cumbria's largest settlement and county town is Carlisle. It consists of six districts, and in...

, North Wales
North Wales
North Wales is the northernmost unofficial region of Wales. It is bordered to the south by the counties of Ceredigion and Powys in Mid Wales and to the east by the counties of Shropshire in the West Midlands and Cheshire in North West England...

, Scotland and Northern Ireland
Northern Ireland
Northern Ireland is one of the four countries of the United Kingdom. Situated in the north-east of the island of Ireland, it shares a border with the Republic of Ireland to the south and west...

... 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.


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.

In Norway, the Sami people
Sami people
The Sami people, also spelled Sámi, or Saami, are the arctic indigenous people inhabiting Sápmi, which today encompasses parts of far northern Sweden, Norway, Finland, the Kola Peninsula of Russia, and the border area between south and middle Sweden and Norway. The Sámi are Europe’s northernmost...

 were affected by contaminated food (the reindeer
Reindeer
The reindeer , also known as the caribou in North America, is a deer from the Arctic and Subarctic, including both resident and migratory populations. While overall widespread and numerous, some of its subspecies are rare and one has already gone extinct.Reindeer vary considerably in color and size...

 had been contaminated by eating lichen
Lichen
Lichens are composite organisms consisting of a symbiotic organism composed of a fungus with a photosynthetic partner , usually either a green alga or cyanobacterium...

, which are very sensitive to radioactivity).

Effect on the natural world

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
Becquerel
The becquerel is the SI-derived unit of radioactivity. One Bq is defined as the activity of a quantity of radioactive material in which one nucleus decays per second. The Bq unit is therefore equivalent to an inverse second, s−1...

/m². The so-called "Red Forest
Red Forest
The Red Forest , formerly the Worm Wood Forest, refers to the trees in the 10 km² surrounding the Chernobyl Nuclear Power Plant. The name 'Red Forest' comes from the ginger-brown colour of the pine trees after they died following the absorption of high levels of radiation from the Chernobyl...

" of pine trees, 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
Red Forest
The Red Forest , formerly the Worm Wood Forest, refers to the trees in the 10 km² surrounding the Chernobyl Nuclear Power Plant. The name 'Red Forest' comes from the ginger-brown colour of the pine trees after they died following the absorption of high levels of radiation from the Chernobyl...

 remains one of the most contaminated areas in the world.

In recent years there have been many reports suggesting the zone may be a fertile habitat for wildlife. 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.

Barn swallows
Barn Swallow
The Barn Swallow is the most widespread species of swallow in the world. It is a distinctive passerine bird with blue upperparts, a long, deeply forked tail and curved, pointed wings. It is found in Europe, Asia, Africa and the Americas...

 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. "This was a big surprise to us," Dr. Mousseau said. "We had no idea of the impact."

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. 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
Source-sink dynamics
Source-sink dynamics is a theoretical model used by ecologists to describe how variation in habitat quality may affect the population growth or decline of organisms....

 populations; in other words, that the apparently healthy populations are not contributing to the survival of species.

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
Cryptococcus neoformans
Cryptococcus neoformans is an encapsulated yeast that can live in both plants and animals. Its teleomorph is Filobasidiella neoformans, a filamentous fungus belonging to the class Tremellomycetes. It is often found in pigeon excrement....

and Cladosporium
Cladosporium
Cladosporium is a genus of fungi including some of the most common indoor and outdoor molds. Species produce olive-green to brown or black colonies, and have dark-pigmented conidia that are formed in simple or branching chains....

, can actually thrive in a radioactive environment, growing better than non-melanized variants, implying that they use melanin
Melanin
Melanin is a pigment that is ubiquitous in nature, being found in most organisms . In animals melanin pigments are derivatives of the amino acid tyrosine. The most common form of biological melanin is eumelanin, a brown-black polymer of dihydroxyindole carboxylic acids, and their reduced forms...

 to harness the energy of ionizing radiation from the reactor.

The Chernobyl Forum report and criticisms

In September 2005, a comprehensive report was published by the Chernobyl Forum
Chernobyl Forum
The Chernobyl Forum is the name of a group of UN agencies, founded on 3–5 February 2003 at the IAEA Headquarters in Vienna, to scientifically assess the health effects and environmental consequences of the Chernobyl accident and to issue factual, authoritative reports on its environmental...

, comprising a number of agencies including the International Atomic Energy Agency
International Atomic Energy Agency
The International Atomic Energy Agency is an international organization that seeks to promote the peaceful use of nuclear energy, and to inhibit its use for any military purpose, including nuclear weapons. The IAEA was established as an autonomous organization on 29 July 1957...

 (IAEA), the World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...

 (WHO), United Nations
United Nations
The United Nations is an international organization whose stated aims are facilitating cooperation in international law, international security, economic development, social progress, human rights, and achievement of world peace...

 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.

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.""

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. For full coverage see the IAEA Focus Page.

The methodology of the Chernobyl Forum report has been disputed by some advocacy organizations opposed to nuclear energy, such as Greenpeace
Greenpeace
Greenpeace is a non-governmental environmental organization with offices in over forty countries and with an international coordinating body in Amsterdam, The Netherlands...

 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
International Agency for Research on Cancer
The International Agency for Research on Cancer is an intergovernmental agency forming part of the World Health Organisation of the United Nations....

, Dr. Michel Fernex
Michel Fernex
Michel Fernex is a Swiss medical doctor, from the Medical Faculty University of Basel. He is a member of Physicians for Social Responsibility and International Physicians for the Prevention of Nuclear War. He was a member of the Steering Committee on Tropical Diseases Research in the World Health...

, 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
Alliance '90/The Greens
Alliance '90/The Greens is a green political party in Germany, formed from the merger of the German Green Party and Alliance 90 in 1993. Its leaders are Claudia Roth and Cem Özdemir...

 Member of the European Parliament
Member of the European Parliament
A Member of the European Parliament is a person who has been elected to the European Parliament. The name of MEPs differ in different languages, with terms such as europarliamentarian or eurodeputy being common in Romance language-speaking areas.When the European Parliament was first established,...

 Rebecca Harms
Rebecca Harms
Rebecca Harms is a German politician and Member of the European Parliament for Alliance '90/The Greens, part of the European Greens. In July 2009 she was elected as co-president of the The Greens–European Free Alliance group in the European parliament.Harms began her career as an apprentice...

, 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)


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.

Another study claims possible heightened mortality in Sweden.

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". 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,".

According to the Union Chernobyl, the main organization of liquidators, 10% of the 600,000 liquidators are now dead, and 165,000 disabled.

According to a April 2006 report by the International Physicians for Prevention of Nuclear Warfare (IPPNW), entitled "Health Effects of Chernobyl - 20 years after the reactor catastrophe", 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
Teratology
Teratology is the study of abnormalities of physiological development. It is often thought of as the study of human birth defects, but it is much broader than that, taking in other non-birth developmental stages, including puberty; and other non-human life forms, including plants.- Etymology :The...

 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.

Controversy over human health effects

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. It will be impossible to attribute specific deaths to Chernobyl , and many estimates indicate that the rate of excess deaths will be so small as to be statistically undetectable, even if the ultimate number of extra premature deaths is large. Furthermore, 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.

The Chernobyl Forum report

In September 2005, a draft summary report by the Chernobyl Forum, comprising a number of UN agencies including the International Atomic Energy Agency
International Atomic Energy Agency
The International Atomic Energy Agency is an international organization that seeks to promote the peaceful use of nuclear energy, and to inhibit its use for any military purpose, including nuclear weapons. The IAEA was established as an autonomous organization on 29 July 1957...

 (IAEA), the World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...

 (WHO), the United Nations Development Programme
United Nations Development Programme
The United Nations Development Programme is the United Nations' global development network. It advocates for change and connects countries to knowledge, experience and resources to help people build a better life. UNDP operates in 177 countries, working with nations on their own solutions to...

 (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. 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. 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. This report is not free of controversy, and has been accused of trying to minimize the consequences of the accident.

The TORCH report

In 2006 German Green Party
Alliance '90/The Greens
Alliance '90/The Greens is a green political party in Germany, formed from the merger of the German Green Party and Alliance 90 in 1993. Its leaders are Claudia Roth and Cem Özdemir...

 Member of the European Parliament
Member of the European Parliament
A Member of the European Parliament is a person who has been elected to the European Parliament. The name of MEPs differ in different languages, with terms such as europarliamentarian or eurodeputy being common in Romance language-speaking areas.When the European Parliament was first established,...

 Rebecca Harms
Rebecca Harms
Rebecca Harms is a German politician and Member of the European Parliament for Alliance '90/The Greens, part of the European Greens. In July 2009 she was elected as co-president of the The Greens–European Free Alliance group in the European parliament.Harms began her career as an apprentice...

 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.

Greenpeace

Greenpeace
Greenpeace
Greenpeace is a non-governmental environmental organization with offices in over forty countries and with an international coordinating body in Amsterdam, The Netherlands...

 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. 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
Endocrine system
In physiology, the endocrine system is a system of glands, each of which secretes a type of hormone directly into the bloodstream to regulate the body. The endocrine system is in contrast to the exocrine system, which secretes its chemicals using ducts. It derives from the Greek words "endo"...

 problems, and particularly effects on the immune system
Immune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...

," will also cause fatalities. However, concern has been expressed about the methods used in compiling the Greenpeace report.

The April 2006 IPPNW report

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
Teratology
Teratology is the study of abnormalities of physiological development. It is often thought of as the study of human birth defects, but it is much broader than that, taking in other non-birth developmental stages, including puberty; and other non-human life forms, including plants.- Etymology :The...

 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.

New York Academy of Sciences publication

Chernobyl: Consequences of the Catastrophe for People and the Environment
Chernobyl: Consequences of the Catastrophe for People and the Environment
Chernobyl: Consequences of the Catastrophe for People and the Environment is a translation of a 2007 Russian publication by Alexey V. Yablokov, Vassily B. Nesterenko, and Alexey V. Nesterenko...

is an English translation of the 2007 Russian publication Chernobyl. It was published online in 2009 by the New York Academy of Sciences
New York Academy of Sciences
The New York Academy of Sciences is the third oldest scientific society in the United States. An independent, non-profit organization with more than members in 140 countries, the Academy’s mission is to advance understanding of science and technology...

 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. 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. Author Alexy V. Yablokov was also one of the general editors on the Greenpeace
Greenpeace
Greenpeace is a non-governmental environmental organization with offices in over forty countries and with an international coordinating body in Amsterdam, The Netherlands...

 commissioned report also criticizing the Chernobyl Forum finds published one year prior to the Russian language version of this report.

The 2011 UNSCEAR report

The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) produced a report http://www.unscear.org/docs/reports/2008/11-80076_Report_2008_Annex_D.pdf 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
Thyroid cancer
Thyroid neoplasm is a neoplasm or tumor of the thyroid. It can be a benign tumor such as thyroid adenoma, or it can be a malignant neoplasm , such as papillary, follicular, medullary or anaplastic thyroid cancer. Most patients are 25 to 65 years of age when first diagnosed; women are more affected...

 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

  • 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. 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
    Belarus
    Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,...

     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.
  • Study of heightened mortality in Sweden.
  • One study reports increased levels of birth defects in Germany and Finland in the wake of the accident.
  • A change in the human sex ratio at birth in several European countries has been linked to Chernobyl fallout.

  • In the Czech Republic, thyroid cancer has increased significantly after Chernobyl.

  • A report from the European Committee on Radiation Risk
    European Committee on Radiation Risk
    The European Committee on Radiation Risk is an informal committee formed in 1997 following a meeting by the European Green Party at the European Parliament to review the Council of Europe's directive 96/29Euratom, issued in May of the previous year....

     (a body sponsored by the European Green Party
    European Greens–European Free Alliance
    The Greens European Free Alliance is one of the parliamentary groups in the European Parliament....

    ) claims that the World Health Organization
    World Health Organization
    The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...

    , 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.
  • The Abstract of the April 2006 International Agency for Research on Cancer
    International Agency for Research on Cancer
    The International Agency for Research on Cancer is an intergovernmental agency forming part of the World Health Organisation of the United Nations....

     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." 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 interval
    Confidence interval
    In statistics, a confidence interval is a particular kind of interval estimate of a population parameter and is used to indicate the reliability of an estimate. It is an observed interval , in principle different from sample to sample, that frequently includes the parameter of interest, if the...

    s from 6,700 deaths to 38,000.

  • The application of the linear no threshold model to predict deaths from low levels of exposure to radiation was disputed in a BBC
    BBC
    The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...

     (British Broadcasting Corporation) Horizon documentary, broadcast on July 13, 2006. It offered statistical evidence to suggest that there is an exposure threshold of about 200 millisieverts
    Sievert
    The sievert is the International System of Units SI derived unit of dose equivalent radiation. It attempts to quantitatively evaluate the biological effects of ionizing radiation as opposed to just the absorbed dose of radiation energy, which is measured in gray...

    , below which there is no increase in radiation-induced disease. Indeed it went further, reporting research from Professor Ron Chesser of Texas Tech University
    Texas Tech University
    Texas Tech University, often referred to as Texas Tech or TTU, is a public research university in Lubbock, Texas, United States. Established on February 10, 1923, and originally known as Texas Technological College, it is the leading institution of the Texas Tech University System and has the...

    , which suggests that low exposures to radiation can have a protective effect
    Radiation hormesis
    Radiation hormesis is the hypothesis that low doses of ionizing radiation are beneficial, stimulating the activation of repair mechanisms that protect against disease, that are not activated in absence of ionizing radiation...

    . 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
    World Health Organization
    The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...

     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
    Peter Boyle (epidemiologist)
    Prof. Peter Boyle, BSc PhD DSc DSc FRSE FFPH FRCPS FRCP FMedSci, is a British epidemiologist. He has done research on globalization of cancer, where he has shown the dramatic increase of cancer in low- and medium income countries.-Biography:Boyle was born in Glasgow, Scotland and studied...

    , director of the IARC
    International Agency for Research on Cancer
    The International Agency for Research on Cancer is an intergovernmental agency forming part of the World Health Organisation of the United Nations....

    : "Tobacco smoking will cause several thousand times more cancers in the [European] population."
  • Professor Wade Allison
    Wade Allison
    Wade Allison is Emeritus Professor of Physics at Oxford University. Author of Radiation and Reason: The Impact of Science on a Culture of Fear.-Early life:...

     of Oxford University (a lecturer in medical physics
    Medical physics
    Medical physics is the application of physics to medicine. It generally concerns physics as applied to medical imaging and radiotherapy, although a medical physicist may also work in many other areas of healthcare...

     and particle physics
    Particle physics
    Particle physics is a branch of physics that studies the existence and interactions of particles that are the constituents of what is usually referred to as matter or radiation. In current understanding, particles are excitations of quantum fields and interact following their dynamics...

    ) gave a talk on ionising radiation Nov 24, 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
    Radiation therapy
    Radiation therapy , radiation oncology, or radiotherapy , sometimes abbreviated to XRT or DXT, is the medical use of ionizing radiation, generally as part of cancer treatment to control malignant cells.Radiation therapy is commonly applied to the cancerous tumor because of its ability to control...

    , exposure to elevated natural radiation (the presence of radon gas
    Radon
    Radon is a chemical element with symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas, occurring naturally as the decay product of uranium or thorium. Its most stable isotope, 222Rn, has a half-life of 3.8 days...

     in homes) and the diseases of Hiroshima and Nagasaki survivors he demonstrated that the linear no-threshold model
    Linear no-threshold model
    The linear no-threshold model is a method for predicting the long term, biological damage caused by ionizing radiation and is based on the assumption that the risk is directly proportional to the dose at all dose levels....

     should not be applied to low-level exposure in humans, as it ignores the well-known natural repair mechanisms of the body.
  • A photographic essay by photojournalist Paul Fusco
    Paul Fusco (photographer)
    Paul Fusco is an American photojournalist who has been associated with Magnum Photos since 1973.-Biography:Fusco was born in Leominster, Massachusetts in 1930 and started pursuing photography as a hobby in 1945. During the Korean War from 1951 to 1953 he gained more experience with it as he worked...

     documents the legacy of the meltdown on local children
  • Y. I. Bandashevsky, Pathology of Incorporated Ionizing Radiation (Belarus Technical University, Minsk. 136 pp., 1999). 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. "For his pioneering work, Bandashevsky was arrested in 2001 and imprisoned for five years of an eight year sentence," said a report by researchers on radiation effects of the Fukushima Daiichi nuclear disaster
    Fukushima Daiichi nuclear disaster
    The is a series of equipment failures, nuclear meltdowns, and releases of radioactive materials at the Fukushima I Nuclear Power Plant, following the Tōhoku earthquake and tsunami on 11 March 2011. The plant comprises six separate boiling water reactors originally designed by General Electric ,...

     in 2011.

French legal action

Since March 2001, 400 lawsuits have been filed in France against "X" (the French equivalent of John Doe
John Doe
The name "John Doe" is used as a placeholder name in a legal action, case or discussion for a male party, whose true identity is unknown or must be withheld for legal reasons. The name is also used to refer to a male corpse or hospital patient whose identity is unknown...

, 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
Thyroid cancer
Thyroid neoplasm is a neoplasm or tumor of the thyroid. It can be a benign tumor such as thyroid adenoma, or it can be a malignant neoplasm , such as papillary, follicular, medullary or anaplastic thyroid cancer. Most patients are 25 to 65 years of age when first diagnosed; women are more affected...

 or goitre
Goitre
A goitre or goiter , is a swelling in the thyroid gland, which can lead to a swelling of the neck or larynx...

s, and have filed lawsuits alleging that the French government, at the time led by Prime Minister
Prime Minister of France
The Prime Minister of France in the Fifth Republic is the head of government and of the Council of Ministers of France. The head of state is the President of the French Republic...

 Jacques Chirac
Jacques Chirac
Jacques René Chirac is a French politician who served as President of France from 1995 to 2007. He previously served as Prime Minister of France from 1974 to 1976 and from 1986 to 1988 , and as Mayor of Paris from 1977 to 1995.After completing his studies of the DEA's degree at the...

, 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
Institut de radioprotection et de sûreté nucléaire
The French Institut de radioprotection et de sûreté nucléaire is a public official establishment with an industrial and commercial aspect created by the AFSSE Act and by the February 22, 2002 decreed n°2002-254...

 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.

Comparisons to other radioactivity releases

See also

  • Bellesrad
    Bellesrad
    Bellesrad is short name for the State Institution for Radiation Monitoring and Radiation Safety of the Republic of Belarus. It is subordinated to the State Forestry Committee of the Council of Ministers of Republic of Belarus...

  • Chernobyl Children's Project (UK)
    Chernobyl Children's Project (UK)
    Chernobyl Children's Project is a UK registered charity based in Glossop, Derbyshire. The charity brings children to the UK for recuperative holidays; many of the children are in remission from cancer or suffer from chronic conditions such as epilepsy or diabetes.CCP was founded in 1995 by Linda...

  • Chernobyl disaster
    Chernobyl disaster
    The Chernobyl disaster was a nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in Ukraine , which was under the direct jurisdiction of the central authorities in Moscow...

  • Chernobyl compared to other radioactivity releases
    Chernobyl compared to other radioactivity releases
    This article compares the radioactivity release and decay from the Chernobyl disaster with various other events which involved a release of uncontrolled radioactivity.-Chernobyl compared to background radiation:...

  • Chernobyl Heart
    Chernobyl Heart
    Chernobyl Heart is a 2003 documentary film by Maryann DeLeo. The film won the Best Documentary Short Subject award at the 2004 Academy Awards....

  • Chernobyl in the popular consciousness
    Chernobyl in the popular consciousness
    The Chernobyl disaster, which occurred on April 26, 1986, was the world's greatest nuclear accident.-Literature:* The disaster is the plot-driving device in the 1988 Marvel Comics miniseries Meltdown, featuring Wolverine and Havok....

  • Chernobyl necklace
    Chernobyl necklace
    Chernobyl necklace is a horizontal scar left on the base of the neck after a surgery to remove a malignant thyroid gland caused by radiation poisoning...

  • Chernobyl Shelter Fund
    Chernobyl Shelter Fund
    The Chernobyl Shelter Fund was set up in December 1997 with the purpose of funding the Shelter Implementation Plan . The main objective of the SIP, developed in a co-operative effort between the European Union, the United States and Ukraine, is to protect the personnel, population and environment...

  • Chernobyl Children's Project International
    Chernobyl Children's Project International
    Chernobyl Children's Project International is a United Nations-accredited international development, medical, and humanitarian organization that works with children, families and communities that continue to be affected by the Chernobyl nuclear disaster of 1986.- Purpose :The organization was...

  • Deaths due to the Chernobyl disaster
    Deaths due to the Chernobyl disaster
    The Chernobyl disaster , was a nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant In the Ukrainian Soviet Socialist Republic , now in Ukraine...

  • Acute radiation syndrome
  • Ionizing radiation
    Ionizing radiation
    Ionizing radiation is radiation composed of particles that individually have sufficient energy to remove an electron from an atom or molecule. This ionization produces free radicals, which are atoms or molecules containing unpaired electrons...

  • Fission products, a more complete description of the radioactive byproducts of nuclear reactors
  • Liquidator (Chernobyl)
    Liquidator (Chernobyl)
    Liquidators , or "clean-up workers", is the name given in the former USSR to people who were called upon to work in efforts to deal with consequences of the April 26, 1986, Chernobyl disaster on the site of the event...

  • List of Chernobyl-related articles
  • Nuclear and radiation accidents
    Nuclear and radiation accidents
    A nuclear and radiation accident is defined by the International Atomic Energy Agency as "an event that has led to significant consequences to people, the environment or the facility...

  • Nuclear power debate
    Nuclear power debate
    The nuclear power debate is about the controversy which has surrounded the deployment and use of nuclear fission reactors to generate electricity from nuclear fuel for civilian purposes...

  • Radiophobia
    Radiophobia
    Radiophobia is an abnormal fear of ionizing radiation, in particular, fear of X-rays. The term is also used in a non-medical sense to refer to general opposition to the use of nuclear energy....

  • Red Forest
    Red Forest
    The Red Forest , formerly the Worm Wood Forest, refers to the trees in the 10 km² surrounding the Chernobyl Nuclear Power Plant. The name 'Red Forest' comes from the ginger-brown colour of the pine trees after they died following the absorption of high levels of radiation from the Chernobyl...

  • Three Mile Island accident
    Three Mile Island accident
    The Three Mile Island accident was a core meltdown in Unit 2 of the Three Mile Island Nuclear Generating Station in Dauphin County, Pennsylvania near Harrisburg, United States in 1979....

  • Three Mile Island accident health effects
    Three Mile Island accident health effects
    The health effects of the 1979 Three Mile Island nuclear accident are widely, but not universally, agreed to be very low level. According to the official radiation release figures, average local radiation exposure was equivalent to a chest X-ray, and maximum local exposure equivalent to less than a...

  • Yury Bandazhevsky, a Belarusian scientist imprisoned from 2001 to 2005 after his publication of a report critical of the official investigation on the consequences of the Chernobyl disaster

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK