Details Parent category: Exclusion zone Category: Radioactive contamination
The consequences of the release of the radioisotope 131 I after the Chernobyl accident and a description of the biological effect of radioiodine on the human body are presented.
Biological action of radioiodine
Iodine-131- radionuclide with a half-life of 8.04 days, beta and gamma emitter. Due to its high volatility, almost all of the iodine-131 present in the reactor (7.3 MKi) was released into the atmosphere. Its biological action is associated with the features of functioning thyroid gland. Its hormones - thyroxine and triiodothyroyain - contain iodine atoms. Therefore, normally the thyroid gland absorbs about 50% of the iodine entering the body. Naturally, iron does not distinguish radioactive isotopes of iodine from stable ones. The thyroid gland of children is three times more active in absorbing radioiodine that has entered the body. Besides, iodine-131 easily crosses the placenta and accumulates in the fetal gland.
The accumulation of large amounts of iodine-131 in the thyroid gland leads to radiation injury secretory epithelium and to hypothyroidism - thyroid dysfunction. The risk of malignant degeneration of tissues also increases. The minimum dose at which there is a risk of developing hypothyroidism in children is 300 rad, in adults - 3400 rad. The minimum doses at which there is a risk of developing thyroid tumors are in the range of 10-100 rad. The risk is greatest at doses of 1200-1500 rad. In women, the risk of developing tumors is four times higher than in men, in children three to four times higher than in adults.
The magnitude and rate of absorption, the accumulation of the radionuclide in organs, the rate of excretion from the body depend on age, gender, the content of stable iodine in the diet, and other factors. In this regard, when the same amount of radioactive iodine enters the body, the absorbed doses differ significantly. Especially large doses are formed in thyroid gland children, which is associated with the small size of the body, and can be 2-10 times higher than the dose of irradiation of the gland in adults.
Prevention of the intake of iodine-131 in the human body
Effectively prevents the entry of radioactive iodine into the thyroid gland by taking stable iodine preparations. At the same time, the gland is completely saturated with iodine and rejects radioisotopes that have entered the body. Taking stable iodine even 6 hours after a single intake of 131 I can reduce the potential dose to the thyroid gland by about half, but if iodine prophylaxis is postponed for a day, the effect will be small.
Admission iodine-131 in the human body can occur mainly in two ways: inhalation, i.e. through the lungs, and orally through consumed milk and leafy vegetables.
Environmental pollution 131 I after the Chernobyl accident
Intense prolapse 131 I in the city of Pripyat apparently began on the night of April 26-27. Its entry into the body of the inhabitants of the city occurred by inhalation, and therefore depended on the time spent on outdoors and the degree of ventilation of the premises.
The situation in the villages that fell into the zone of radioactive fallout was much more serious. Due to the ambiguity of the radiation situation, not all rural residents received iodine prophylaxis in a timely manner. The main route of entry131 I in the body was food, with milk (up to 60% according to some data, according to other data - up to 90%). This radionuclide appeared in the milk of cows already on the second or third day after the accident. It should be noted that a cow daily eats food from an area of 150 m 2 on pasture and is an ideal concentrator of radionuclides in milk. On April 30, 1986, the USSR Ministry of Health issued recommendations on a general ban on the consumption of milk from pasture cows in all areas adjacent to the accident zone. In Belarus, cattle were still kept in stalls, but in Ukraine, cows were already grazed. At state-owned enterprises, this ban worked, but on private farms, prohibition measures usually work worse. It should be noted that in Ukraine then about 30% of milk was consumed from personal cows. In the very first days, a standard was set for the content of iodine-13I in milk, under which the dose to the thyroid gland should not exceed 30 rem. In the first weeks after the accident, the concentration of radioiodine in individual samples of milk exceeded this standard by tens and hundreds of times.
Imagine the scale of pollution natural environment iodine-131 can help such facts. According to existing standards, if the density of pollution in a pasture reaches 7 Ci/km 2, the consumption of contaminated products should be excluded or limited, livestock should be transferred to unpolluted pastures or forage. On the tenth day after the accident (when one half-life of iodine-131 had passed), Kyiv, Zhytomyr and Gomel regions of the Ukrainian SSR, the entire west of Belarus, the Kaliningrad region, west Lithuania and northeast Poland fell under this standard.
If the pollution density lies within 0.7-7 Ci/km2, then the decision should be made depending on the specific situation. Such pollution densities were almost throughout the Right-Bank Ukraine, throughout Belarus, the Baltic states, in the Bryansk and Oryol regions of the RSFSR, in the east of Romania and Poland, southeast Sweden and southwest Finland.
Emergency care for radioiodine contamination.
When working in an area contaminated with radioisotopes of iodine, for the purpose of prevention, daily intake of potassium iodide 0.25 g (under medical supervision). Decontamination of the skin with soap and water, washing the nasopharynx and oral cavity. When radionuclides enter the body - inside potassium iodide 0.2 g, sodium iodide 02.0 g, siodin 0.5 or tereostatics (potassium perchlorate 0.25 g). Vomiting or gastric lavage. Expectorants with repeated administration of iodine salts and stereostatics. Plentiful drink, diuretics.
Literature:
Chernobyl does not let go… (to the 50th anniversary of radioecological research in the Komi Republic). - Syktyvkar, 2009 - 120 p.
Tikhomirov F.A. Radioecology of iodine. M., 1983. 88 p.
Cardis et al., 2005. Risk of Thyroid Cancer After Exposure to 131I in Childhood -- Cardis et al. 97 (10): 724 -- JNCI Journal of the National Cancer Institute
Almost 30 years ago, the attention of the world was riveted to itself - the Ukrainian city in which the nuclear power plant which was the worst nuclear disaster in the world.
The world has come a long way since that horrific event in 1986, but one thing hasn't really changed in the polluted Chernobyl: dead trees and leaves. They do not even approximately decompose at the same rate as flora elsewhere in the world.
“We were stepping over all those dead trees on the ground that had been knocked down by the first explosion,” says Tim Musso, professor of biology at the University of South Carolina. - Years later, these trunks are perfectly preserved. If a tree fell in my garden, in 10 years it would turn into dust.
Tim Musso and his colleague Anders Müller of the University of Paris-South have conducted long-term studies on the biology of radioactive regions such as Chernobyl and Fukushima, Japan.
Much of their work took place in the Red Forest, the infamous wooded region around Chernobyl, where the trees turned an ominous reddish-brown color before they died. The scientists noted that the tree trunks appear to have largely remained unchanged, even after two and a half decades have passed.
“With a few exceptions, almost all of the dead tree trunks were intact when we first encountered them,” says Tim Musso, who is also head of the Chernobyl and Fukushima Research Center.
To find out what happened, or rather, NOT happened, the researchers collected hundreds of samples that had not been exposed to radiation and packed them in insect-proof bags. Then they distributed them throughout the Chernobyl area and left them for nine months.
The results were astounding: leaf litter samples left in areas with high levels of pollution showed decay rates 40 percent lower than leaves left in uncontaminated areas. In all plots, the degree of decomposition was proportional to the level radioactive contamination.
Radiation is known to adversely affect microorganisms such as bacteria and fungi. A recent study has shown that radiation therapy can cause serious complications due to a decrease in the population of beneficial bacteria in the gut. 
Musso and others are concerned that the accumulation of fallen leaves on the ground in the forest is a real danger. “We have growing suspicions that a catastrophic fire will occur in the coming years,” the scientist notes.
In the event of a forest fire, leaves that have not decomposed in 28 years will be an ideal fuel, and the fire will spread radiation throughout the region. “As a result, radiocesium and other pollutants with smoke will enter the settlements,” Musso emphasizes.
“Leaf litter, apparently due to reduced microbial activity, is an excellent kindling material,” the scientist added. “They are dry, light and burn great. This proves once again that it can begin
I remember how April 27, 1986 and we at the Institute of Biological Physics in Moscow adopted 250 casualties. The people arrived on two special flights. These two planes were later destroyed because they were very dirty.
These memories of the first days after the accident during the International Scientific and Practical Conference in Gomel “25 years after the Chernobyl disaster. Overcoming its consequences within the framework of the Union State” shared Leonid Ilyin- Russian academician, now honorary president of the Federal Medical Biophysical Center named after A. I. Burnazyan, Doctor of Medical Sciences, Professor. From the first days and during the most difficult period of the Chernobyl accident, he worked in the lesion site, was one of the scientific supervisors of biomedical and hygienic work to mitigate the consequences of the accident, made fundamental decisions on the strategy and tactics of protecting people:
More than 100 employees have been treated in our clinic Chernobyl power plant. Dose rate from some patients reached up to 1 roentgen per hour. As for the Chernobyl station and our time spent there during the most difficult period, the meteorological academician and I Yuri Israel discussed all the problems associated with the movement of air masses. He is a professional in this business. I realized that the first plume went to the West, and - mysticism - it went around the city of Pripyat, which is located next to Chernobyl. This was explained by the fact that the air temperature in the city is slightly higher than in the surrounding area. And this cloud bypassed the city of Pripyat. According to our calculations, if there had been no evacuation on April 27, then by the end of the week, the population of the city would have obvious conditioned radiation damage. It was very difficult to figure out how these air masses, which went north, approached the settlements of the Gomel region and Gomel. Air masses began to spin around Gomel. The specific concentration of radioactive substances was increased, because within 10 days a large number of radioactive materials. Now there are a variety of estimates of emission levels. One thing is clear: it was a tragedy not only of Chernobyl, but of the entire population of the Gomel region. Was a complete failure in the organization of iodine prophylaxis. Let me remind you that 19 years before the accident, we developed a system of iodine prophylaxis. But required document did not reach for unknown reasons to those who could use it. Thus, iodine prophylaxis was not carried out in the Gomel region. Therefore, we got high dose loads, including in children. Against this background, many radiological problems arose. And that is why the idea of creating a center for radiation medicine and human ecology in Gomel causes a feeling of pride in us and a feeling of envy in our foreign colleagues. Moreover, not only residents of the Gomel region, but also the whole of Belarus undergo medical examination and treatment here.
Staff Republican Scientific and Practical Center for Radiation Medicine and Human Ecology, which is located in Gomel, are doing a lot of scientific work and for the eighth time in April they are holding a traditional scientific conference dedicated to the medical consequences of the Chernobyl accident.
State Register of Citizens Affected by the Chernobyl Disaster, was founded in 1993. The purpose of its creation was to ensure control over the state of health and obtain information about the medical and biological consequences of the disaster on Chernobyl nuclear power plant, as well as other radiation accidents. This database is constantly updated with the necessary information about diseases and treatment of people. It contains information about dispensary examinations and radiation doses. To date, at the republican level of the state register, information has been accumulated on 282 thousand people, which belong to the most exposed categories of the affected population. Information from the State Register is used to study the structure, dynamics, trends in morbidity, disability, outcomes of diseases of citizens, analysis and control of medical examinations in government organizations health care, development of methods and criteria for determining groups of increased radiation risk based on a comprehensive radiation-epidemiological and statistical analysis.
Back in the early 1990s, as a result of thyroid dosimetric certification were reconstructed average thyroid doses for more than 9.5 million people who then lived in 23 thousand settlements republics. It was revealed that almost the entire population of the country was exposed to iodine radionuclides to one degree or another, says the director of the Republican Scientific and Practical Center for Radiation Medicine and Human Ecology, Candidate of Medical Sciences, Associate Professor Alexander Rozhko:
It should be emphasized that in none of the categories of the affected population the average effective accumulated radiation doses for the entire post-accident period did not exceed 80-100 mSv. Obviously, as a result of the protective measures taken, the level of public exposure is significantly below the threshold for the occurrence of any specific effects. Throughout the country is carried out special medical examination. It concerns those citizens who belong to the affected population, and today it is 1.5 million people. Every year, each victim undergoes a dispensary examination. According to medical indications, the reception of injured citizens is carried out by specialists of the required profile, including in our Republican Scientific and Practical Center for Radiation Medicine and Human Ecology. The same applies to the possibility of inpatient treatment of any disease.
- Who is at risk today, a quarter of a century after the accident?
Today, among the population affected by the Chernobyl disaster, 3 groups of potential radiation risk have been identified. Group A includes those who, in the early post-accident period (1986) lived or worked within the evacuation zone. This group includes part of the liquidators and the evacuated population. Risk group B consists of those who were at the time of the disaster, regardless of which category of the affected population they belong to. Group B includes those who repeatedly have internal exposure level exceeding 1.0 mSv/year.
- At the conference, information was announced that “there is a class of diseases and a separate group of the population, which has experienced a dramatic increase in the incidence over the past years. Talk about thyroid pathology, and not just thyroid cancer. In almost all analyzed age groups, this dose dependence is present. Benign nodular pathology also has a causal share of disease due to exposure to iodine-131.” Tell us, what deviations in the state of health, including those related to the state of the thyroid gland, manifest themselves 25 years after the accident?
Studies conducted at our institution have shown a direct relationship between the level of thyroid exposure to radioactive isotopes of iodine and the frequency of such thyroid diseases as nodular goiter and thyroid adenoma. However, this effect has so far been evaluated only for those who suffered from exposure. in childhood and adolescence. In general, the structure of primary and general morbidity of the affected population is similar to that of the entire population of Belarus. One of the indicators of the effectiveness of prophylactic medical examinations is the steady decline in primary morbidity over many years. The main factor influencing the change in the levels and structure of the incidence of the affected population is the aging of citizens. This affects the increase in the proportion of cardiovascular and oncological diseases, which, however, should not be associated with the “Chernobyl” impact. The average age in the main groups of the affected population is 10 years or more higher than the national average, which, of course, is the main reason for the higher rates of cancer. For the vast majority of localizations of malignant neoplasms, there is no real outstripping growth in oncological morbidity. It can be stated with certainty that a significant number of additional (radiation-related) cases of thyroid cancer have been registered not only in children and adolescents, but also in the adult affected population. The radiation risk, which is several times higher than spontaneous morbidity, was found in the liquidators and the evacuated population to the greatest extent.
- What are the directions for further activities of the Republican Scientific and Practical Center for Radiation Medicine and Human Ecology?
Priority areas of practical and scientific activity research should be considered filling in the State Register the results of the assessment of radiation doses and radiation-epidemiological data analysis by groups of increased radiation risk, improving the system of medical supervision, special medical examination of various categories of the affected population, taking into account groups of increased radiation risk, as well as the development and implementation of methods for the prevention, early diagnosis, treatment and rehabilitation of oncological and non-oncological diseases in the affected population.
Irina Astashkevich, April 26, 2011.
Newspaper "Zvyazda", original in Belarusian: http://zvyazda.minsk.by/ru/archive/article.php?id=78266&idate=2011-04-26
Our correspondent visited Pripyat and tried to refresh in his and your memory some facts about radiation, which had faded greatly after graduation. He brought the article, but he did not become the Hulk: he returned as skinny and white as he left. And we were hoping...
Theater of Radiation
There are several interesting objects in the Zone: the station itself, the abandoned city of Pripyat and the Russian Woodpecker installation.
The same 4th power unit of the Chernobyl nuclear power plant today looks everyday. Background outside - 5–9 microsieverts per hour (2-3 times higher than in an airplane)
In total, more than 600 thousand people participated in the liquidation. Arriving and gaining an acceptable, and sometimes unacceptable dose, a person retired. The remaining reactors operated for another decade and a half. A new roof was erected on the 4th block, the station was repeatedly washed to a shine, filled with concrete, scattered pieces of fuel were collected and taken out, the layer of soil around was cut off. The work continues to this day and will continue for another fifty years at least.
The tour can even be allowed under the sarcophagus in the ominous block number 4 - not into the reactor hall itself, but to the control panel where the events unfolded. Here is darkness and desolation. Background - 2-13 microsieverts per hour (one minute here is like 1-6 minutes in an airplane, you can live). But particle contamination is strong: several hundred particles per minute per square centimeter. It is impossible to breathe without a respirator, the clothes are special, replaceable.
At the exit - mandatory control of hands, feet and clothes. And this is not the last frame on the way. Radioactive dust is just dust. It is recommended to start by washing your hands with cool water and soap. Atomic workers always wash cold water, as warm expands the pores and dust can clog into the skin for a long time. They also say that nuclear scientists wash their hands twice in the toilet - before and after. And it's not a joke.
The station is full of life, thousands of people from different countries: waste processing and disposal plants are being launched (where to build them, if not here?), a giant arch is being built, which in a couple of years will be rolled onto the reactor so that it can be disassembled. The ultimate goal is the concept of a "green lawn": to disassemble all the uncontrollably glowing horror inside, carefully recycle and bury.
Where to find radiation if you are an alien and cannot live without it
Noticeably phonite any granite. Granite embankments, lined metro stations, slabs in a building materials store - everywhere you can see an elevated background.
Good phonite rhodonite is a stone resembling red granite. In Moscow, for example, he decorated the Mayakovskaya metro station.
Zone of the Chernobyl station, Fukushima, former nuclear test sites.
Household devices. Isotopes are used in fire detectors. The simplest isotope of hydrogen, tritium, which emits beta particles with a half-life of 12 years, can be legally bought in the form of a luminous keychain with the frank name Betalight.
In Moscow, the ravines of the Kolomenskoye Park on the slope of the river, where there used to be a waste disposal site, are fading. There are nuclear burial sites near Sergiev Posad and Podolsk. Yes, and in Moscow there are many institutions with such dirt inside, left over from the experiments of bygone years, that it is scary to enter there.
On this page we have placed a small probe containing the isotope of radiation-404. Try not to touch it with your hands or lick it until you get a home dosimeter.
City of Pripyat
Today, in terms of radiation, Pripyat is thousands, hundreds of thousands times cleaner than in the days after the accident. Tours are taken to the city: here you can walk, breathe without respirators. The biggest danger is falling buildings. It is not recommended to touch objects with your hands, sit on the ground, drink and eat: dust can get in. The city will never come to life. Children will never be able to play in the sandbox here. Grannies will not grow radishes in the beds. Water for drinking and, probably, even for showering will have to be transported from cleaner places. But it is a unique reserve of the era. Perhaps this is the only place on Earth where you can see a piece of the real Soviet Union 80s of the last century.
Surviving frescoes on the walls of crumbling buildings
Monument to firefighters who worked at the Chernobyl nuclear power plant
The dirtiest place in the city is the basement of the city hospital: jackets, helmets and boots are piled here, which the firefighters of that fatal brigade took off when they returned from extinguishing the roof of the block. Everything is covered with soot and particles of nuclear fuel. Even after almost 30 years, clothes are emitting up to one roentgen per hour - it is impossible to enter the basement without special suits and respiratory protection. Almost all the firefighters died within a month, they were buried in lead coffins: the bodies sullied dangerously. Other dirty places in Pripyat are sewers and drains. The rains washed away radioactive dust here for decades.
Test in North Korea that created a 4.9 earthquake
In addition to accidents, there are a couple of thousand nuclear tests all over the world: underground, ground, underwater, atmospheric. There are more than nine hundred in Nevada alone. An emergency with the loss of radioactive parts (for example, in 1987 in Goiania, Brazil, when cretins stole a luminous isotope and rubbed the whole village with it). And also constant emissions from a drying up radioactive reservoir at Mayak in 1960-1985. But even so far there have been no terrorist attacks - nuclear explosions or "dirty bombs" (a conventional explosion that scatters radioactive dirt over the area is easier to make than a nuclear one, and the consequences are not much better). It turns out that at least once every 10 years a nuclear emergency occurs in the world: reactors explode, planes with warheads and satellites with reactors fall, emissions occur. Perhaps you, as a patriot, will be pleased to know that half of all nuclear emergencies occur in our country, in this respect we are ahead of the rest.
Shooting tests in Nevada. USA, April 1952
Disinfection of settlements after the nuclear incident in Goiania. Brazil, 1987
Let's be realistic: no one will refuse nuclear energy (in France, for example, Atom stations give 80% energy). And let's not be naive: accidents can happen in the future, it just makes sense to learn from mistakes. What can you personally do? Only two things.
Get a dosimeter. You live in Russia, where, by the will of fate, dosimeters are of the highest quality and cheapest. By God, you bought so much electronic garbage and gadgets that not buying a dosimeter is just stupid. The cutest of the simple ones is the Togliatti SMG (from $100). Atomists consider the Lviv "Terra" (from $200) to be the most accurate and reliable. And there are all sorts of bluetooth dosimeters.
It is good to understand why radiation is dangerous and what is not dangerous, so as not to succumb to world radiophobia.
What's next for us?
The list of the largest nuclear emergencies looks like this:
1945 - US bombing of the Japanese cities of Hiroshima and Nagasaki
1957 - USSR, accident at the Mayak plant
1957 - UK, Windscale reactor accident
1961 - USSR, accident on the K-19 submarine
1964 - USSR, the fall of the Transit-5V satellite with a nuclear installation
1966 - Spain, the destruction of three nuclear bombs in the village of Palomares
1968 - USA, destruction of four thermonuclear bombs in a plane crash over Greenland
1970 - USSR, accident at the Krasnoye Sormovo plant
1979 - USA, accident at the Three Mile Island nuclear power plant
1980 - USSR, radioactive contamination in Kramatorsk
1985 - USSR, accident in Chazhma Bay
1986 - USSR, Chernobyl accident
2011 - Japan, accident at the Fukushima-1 nuclear power plant
What is commonly called radiation is divided into three types: alpha -
α β γ Gamma radiation and X-rayOf the same nature as light and radio waves. Gamma rays penetrate through everything long distances. Best of all, γ-radiation is weakened by water, concrete, and lead. The natural cosmic background on the planet's surface is about 0.11 microsievert. For an aircraft that has gained altitude, the atmospheric layer ceases to act as a shield, so the natural space background in the aircraft reaches 3 millisieverts anywhere in the cabin, but this is not dangerous. All radiometers measure γ. Sources of γ-radiation: cesium-137, cobalt-60; x-ray hard radiation - americium-241.
beta radiationA stream of electrons or positrons that escape from an atom of a radioactive element. They fly not far, so it is possible to fix β only at close range. Breaking into tissue, the particles cause more damage than gamma rays. From β protects a sheet of aluminum a couple of millimeters, window glass, sometimes even clothing. It is believed that not all household radiometers are able to measure β, but they will still whistle when brought close. Sources of β-radiation: potassium-40, cesium-137, strontium-90; neutron - plutonium.
alpha radiation(uranium, radon, radium, thorium, polonium) - a helium atom flying away. From the point of view of atoms, the thing is quite large and, if it enters the tissue, can do a lot of harm: the harm of α-radiation is 20 times greater than that of γ-radiation. But α flies over a distance of a few millimeters to several centimeters and stops even with a sheet of paper. It is believed that a household dosimeter is not able to detect α-radiation even when brought close. But α rarely walks alone, usually there are always impurities β and γ. Sources of α-radiation: radon, thoron, uranium.
Radiation becomes thousands of times more dangerous if the particles enter the body with air, food, or clog with dust in the skin. From now on, this is a holiday that is always with you. The chance of getting a dangerous dose in some way from the outside is minimal, except to read a book under an X-ray lamp every day.
Gamma backgroundNaturally, it does no noticeable harm until its dose is exceeded by a thousand, or even a million times.
The alpha and beta particles fly close and are stopped by anything. Therefore, in small doses, they do not pose a threat to the body if they do not get inside. Once inside with food and air, the radioactive isotope remains in the body (sometimes forever) in order to systematically bombard the surrounding tissues with particles. The totality of destruction leads to a variety of diseases, especially often to cancer: at some point, the immune system does not have time to cope with its usual work - to constantly identify and remove damaged cells that have decided to become cancerous and begin endless growth.
History knows cases when in areas that were considered radioactively contaminated, mortality, on the contrary, turned out to be noticeably lower than in ordinary ones. Frightened doctors so often dragged residents to medical examinations that early diagnosis and timely treatment brought more health benefits than the purity of nature.
pioneers
Pierre and Marie Curie in the laboratory, 1896
Radioactivity was discovered by Monsieur Becquerel in 1897, in general, by accident: he studied uranium salts and left the substance in a cabinet on a photographic plate. And later I noticed that the plate lit up by itself through the black wrapper. He shared his discovery with his colleagues - the spouses Pierre and Marie Curie, and they discovered radium and polonium. Becquerel discovered the harm of radiation to health later, but in the same way: he borrowed a test tube with radium from Curie and carried it in his vest pocket, and later noticed reddening in the form of a test tube on his skin. He shared this again with Pierre Curie. He strapped a test tube with a fair amount of radium to his shoulder and wore it for ten hours, earning a serious ulcer for the next couple of months.
Despite the fact that scientists have been working with radiation all their lives, it is wrong to assume that radiation killed them. Becquerel died unexpectedly at the age of 55 (during a trip with his wife), and the cause of death is unknown. Pierre Curie, at the age of 46, slipped and got hit by a horse. Marie Curie certainly died of radiation-induced leukemia - the pages of her laboratory diary are still glowing in the museum in such a way that it is scary to approach them. But Maria died at the age of 66 - for more than 30 years she worked with radiation after receiving the Nobel Prize for her discovery.
What to do if these idiots again something exploded?
During a nuclear reaction nuclear explosion or leakage from the reactor) many different radioactive substances that will harm all survivors. If you heard the roar of an explosion, then there are two good news: first, you are alive; second, all nuclear reactions have already ended. But the air was filled with radioactive volatile aerosols, and in a few hours all the sensors from hundreds and thousands of kilometers away will howl from them.
On April 26, 1986, the lives of millions of Belarusians, Ukrainians and Russians changed dramatically. This date divided our history into "before" and "after". 22 years ago, the largest nuclear accident in the world occurred at the fourth block of the Chernobyl nuclear power plant .
More than twenty years later, this topic is still painful and relevant. At the same time, it cannot be said that we know enough about what happened.
We want to know more. We must know more.
Therefore, TUT.BY decided to conduct a kind of radiation educational program. We have prepared answers to the most important questions on the topic.
What is radiation?
Radiation (translated from Latin - radiation) in general is an energy that propagates in the form of waves and particles: light, heat, electromagnetic waves. But most often, when people talk about radiation, they mean "ionizing" radiation. Ionizing radiation is so named due to its ability to cause ionization of atoms and molecules in a substance. Ionization is the transformation of neutral particles into electrically charged ones.
Such radiation is emitted by radionuclides - radioactive elements - during "decay".
More than 40 different types of radionuclides were released from the destroyed reactor during the first 10 days after the accident. For the analysis of the consequences of the accident, iodine (J-131), cesium (Cs-137) and strontium (mainly Sr-90) are of primary importance.
Weather conditions in the first days after the accident led to the fact that radioactivity spread widely up to the territories of Scandinavia, Poland, the Baltic states, as well as southern Germany, northern France and England. In Belarus, Russia and Ukraine, heavy rains occurred in places, which led to a very uneven distribution of radionuclides. For example, in the Gomel region of Belarus, northeast of Chernobyl, part of the territory was contaminated to the same extent as the area in the immediate vicinity of the reactor. "Spots" of strong radiation pollution often coexist with slightly contaminated areas.
Iodine-131(with a half-life of 8 days) - was the most dangerous radioactive element in the first weeks after the accident. The human body does not distinguish between radioactive and natural stable iodine and accumulates radioactive iodine mainly in the thyroid gland. Therefore, in the first days after the tragedy, it was important to consume ordinary iodine in order to minimize the possibility of radioactive iodine entering the body.
Cesium-137 ( with a half-life of 30 years) is by far the most common isotope. Between 125,000 and 146,000 square kilometers are considered to be contaminated with radioactive cesium today.
In addition, the danger of long-term radioactive contamination is strontium(Sr-90) with a half-life of 29 years and plutonium(Pu-241), including its degradation products. Some of them will fall apart by half only after 24,000 years!
Radioactive cesium, strontium and plutonium are increasingly distributed along the "soil - plant - animal / human" chain. According to the estimates of the Department for the Elimination of the Consequences of the Chernobyl Disaster, "cesium will remain in the root layers of soil for a long time to come." The most polluted are forest soils.
Strontium is much more mobile than cesium, it dissolves easily in water, and therefore its movements in the soil are less predictable. After the accident, this radioactive element dispersed in a 30-kilometer zone, as well as in the Gomel and Mogilev regions in southern Belarus. To date, Belarusian and foreign experts believe that up to 80% of strontium has already entered the natural cycle of substances.
Radioactivity units
The most common units for measuring soil and food radioactivity are Becquerel (Bq) and Curie (Ci).
Typically, activity is indicated per 1 kg of food. Such activity is called specific.
The maps indicate activity per unit area, for example, km 2 . But the level of contamination of the territory 1Ci/km2 in itself does not say anything about what kind of exposure people living in this territory received. measure harmful effects radioactive radiation per person is the radiation dose, which is measured in Sieverts (Sv).
Term | Units | Unit ratio | Definition |
|
In the SI system | In the old system |
|||
Activity | Becquerel,Bq | 1 Ki = 37 x 109 Bq | number of radioactive decays per unit time |
|
Dose rate | sievert per hour, Sv/h | roentgen per hour, R/h | 1 μR/h=0.01 μSv/h | radiation level per unit time |
Absorbed dose | radian, rad | 1 rad=0.01 Gy | amount of ionizing radiation energy transferred to a particular object |
|
Effective dose | Sievert, Sv | 1 rem=0.01 Sv | radiation dose, taking into account the different sensitivity of organs to radiation |
|
In accordance with our legislation, the permissible radiation dose for the public is 1 mSv per year, and for professionals working with sources of ionizing radiation - 20 mSv per year.
Dose | the effect |
Over 3,000 mSv | Dose life-threatening |
Over 1,000 mSv | Dose that causes radiation sickness |
Over 200 mSv | Dose that increases the risk of various diseases, including cancer (risk increases with dose) |
200 - 500 mSv | Dose with the effect of "radiation hormesis" - there is an improvement in the functioning of the body |
Over 100 mSv | The dose of irradiation of the fetus, at which malformations are possible |
The dose at which positive or negative health changes are not recorded |
To receive a dose of 100 mSv, you need to be in conditions for six months radiation background at 2500 μR/h, this is 250 times higher than the background values (with a normal background of 10 μR/h, a dose of 100 mSv will have to be received for 120 years). The annual dose from watching TV for 3 hours a day is 0.001 mSv. The annual dose from smoking one cigarette a day is 2.7 mSv. One fluorography - 0.6 mSv.; one radiography - 1.3 mSv; one fluoroscopy - 5 mSv.
What foods pose the greatest risk in terms of radiation?
The main reasons for the ingestion of radionuclides in food today are the high content of radionuclides in mushrooms, berries, fish and game, as well as radioactive contamination of grass and hay, which feed cows that give milk. Contamination of meat and milk can be reduced by using clean feed and feed additives, as well as by limiting grazing time. For food from the public sector, as well as products sold in the markets, there are norms for the maximum content of radionuclides.
Republican permissible levels of cesium and strontium radionuclides in food products and drinking water.
Product name | Bq /kg, l | |
For cesium-137 | ||
Drinking water | ||
Condensed and concentrated milk | ||
Cottage cheese and curd products | ||
Rennet and processed cheeses | ||
Corvier oil | ||
Beef, lamb and their products | ||
Pork, poultry and their products | ||
Potato | ||
Bread and bakery products | ||
Flour, cereals, sugar | ||
Vegetable fats | ||
Animal fats and margarine | ||
Vegetables and root crops | ||
garden berries | ||
Canned products from vegetables, fruits and garden berries | ||
Wild berries and canned products from them | ||
Mushrooms fresh | ||
dried mushrooms | ||
Specialized ready-to-eat baby food products | ||
Other food | ||
For strontium-90 | ||
Drinking water | ||
Milk and whole milk products | ||
Bread and bakery products | ||
Potato | ||
Specialized ready-to-eat baby food | ||
Reduce risk radioactive contamination through food you can, if you cook food in a certain way.
Reduction of radioactive contamination of crop products depending on the processing methods
Products | Ways to reduce radioactive contamination | Degree of pollution reduction |
Potatoes, tomatoes, cucumbers | Washing in running water | |
Removal of cover leaves | ||
Beets, carrots, turnips | Cutting the corolla of a root crop | |
Potato | Cleaning the washed tuber | |
Barley, oats (grain) | Irradiation, film removal |
The greatest danger from the point of view of radiation is represented by "gifts of the forest" and products obtained in private farmsteads. The radiation dose of those who eat these products can be several times higher than the average radiation dose for the inhabitants of a given settlement.
The main problem here is the desire or, rather, the unwillingness of the people themselves to take care of their own health and the health of others. Picking berries and mushrooms in polluted regions is an unmanageable issue. According to the chairman of the National Commission for radiation protection at the Council of Ministers, Jacob Koenigsberg: "We can only mark contaminated areas. All this has been done. But our people do not want to change their eating habits. In addition, people go to these areas and earn several thousand dollars a season." By the way, the Poles buy chanterelles with excess radiation levels.
Important, especially if the intake of radionuclides into the body is of a long-term nature, is the use of special preparations or natural products containing similar stable (non-radioactive) elements and reducing the transfer of radionuclides into the human body. For example, preparations containing calcium with vitamin D will protect the bones. In addition, foods rich in potassium (legumes, dried fruits) prevent the deposition of cesium in the body, and calcium-rich foods (milk, eggs, legumes) prevent strontium.
What is the area of the "forbidden zone" and how many people live there?
The "forbidden zone" - the territory on which a special legal status operates, is divided into three parts.
Exclusion Zone- This is a 30-kilometer zone around the Chernobyl nuclear power plant. Human activity is not supposed here at all - for an indefinite time, perhaps for centuries. In 1988, the Polessky State Radiation and Ecological Reserve of the Committee on Problems of the Consequences of the Catastrophe at the Chernobyl Nuclear Power Plant was established in the exclusion zone. About 130,000 Ci of cesium-137 (30 percent of what fell on the territory of Belarus), 12,000 Ci of strontium-90 (73 percent), 400 Ci of plutonium-238,239,240 isotopes (97 percent) are concentrated on the territory of the reserve. Soil pollution density reaches 1350 Ci/sq.km for cesium-137, 70 Ci/sq.km for strontium-90, 5 Ci/sq.km for plutonium and americium-241 isotopes. Due to the presence in ecosystems of significant amounts of long-lived isotopes of plutonium and americium, the main territory of the reserve cannot be returned to economic use even in the long term.
Next is resettlement zone. There is limited human activity here. Basically, it comes down to planting forests in as large an area as possible. Most often in this zone you can meet self-settlers - people who live in it despite the prohibitions. Currently, about 300 people voluntarily live in the resettlement zone.
Next comes the zone with the right to resettlement. If there are those who wish to leave here for safer places, then they are immediately provided with housing there. Every year, the authorities reduce the zone with the right to resettlement, justifying these decisions by reducing the level of radioactive contamination.
In Belarus, 137.6 thousand people were resettled from regions contaminated with radionuclides. 435 villages and hamlets were abandoned by people.
What territories of Belarus are considered contaminated as a result of the Chernobyl accident?
A UN report published in 2005 states that the Chernobyl disaster has claimed and will claim approximately 4,000 lives. However, the report has been heavily criticized by independent experts on the Chernobyl issue, who believe it downplays the harmful effects of Chernobyl disaster.
At present, the connection between the catastrophe and thyroid cancer has been scientifically proven. The number of cases of thyroid cancer among children after the Chernobyl disaster has increased 200 times! It should be noted that Belarus has developed unique techniques thyroid cancer treatment. Even our Japanese colleagues learn from our specialists Evgeny and Yuri Demidchikov.
An increase in the number of cases of breast cancer is also recognized at the international level as a direct consequence of the Chernobyl accident. Statistics confirm the doubling of cases of this disease in the Gomel region of Belarus. Belarusian and Ukrainian scientists predict an increase in the incidence of tumors of the genitourinary system, cancer of the lungs and stomach, both among the liquidators and among the male population of heavily polluted territories.
In Belarus, 70% of all radionuclides released after the 1986 accident fell out. About 22% of the country's territory has been contaminated with radioactive cesium-137. Today, contaminated areas still make up 21% of the territory of the republic. According to the estimates of the Department for the Elimination of the Consequences of the Chernobyl Disaster, by 2016, contaminated areas will account for 16% of the territory of Belarus.
Wild animals in contaminated forests continue to accumulate large amounts of radionuclides as they feed on polluted lichens, berries and mushrooms.
In the first 10 days after the accident, the main carriers of radionuclides, along with rain, were rivers. First of all, this concerned Pripyat and the Dnieper. The concentration of radionuclides in large and medium-sized rivers of Belarus on this moment decreased to such an extent that it does not exceed today the Republican permissible levels - 10 Bq / l.
With the exception of areas inside the exclusion zone, the air inhaled in contaminated areas is clean. However, air pollution from plowing dust, forest fires and wind erosion remains a serious problem both inside and outside the exclusion zone.
Economy
In addition, the tragedy at Chernobyl resulted in multi-billion dollar losses. "240 billion dollars could be a loss for Belarus 30-year rehabilitation period since the accident at the Chernobyl nuclear power plant. This figure was published by the Deputy Minister of Economy Andrey Tur in 2002. This amount is equal to 32 Belarusian budgets in 1985!
Obviously, our country will not soon get rid of the consequences of the Chernobyl disaster. In addition to the tragedy of the national level, many thousands of Belarusians experienced their personal, family tragedies- Lost loved ones, health, home. Empty, ransacked houses, children's toys covered with 20 years of sinister dust, thrown on the floor, someone's photographs
May this never happen again!
TUT.BY would like to thank the Russian-Belarusian information center on the problems of the consequences of the disaster at the Chernobyl nuclear power plant More detailed information about the disaster and its consequences can be found on the website
