The danger of radiation for the human body. How radiation enters the human body. Radiation and radioactivity measuring instruments

Radiation- invisible, inaudible, has no taste, color or smell, and is therefore terrible. Word " radiation»causes paranoia, terror, or a strange state strongly reminiscent of anxiety. With direct exposure to radiation, radiation sickness can develop (at this point, anxiety develops into panic, because no one knows what it is and how to deal with it). It turns out that radiation is deadly... but not always, sometimes even useful.

So what is it? What do they eat it with, this radiation, how to survive an encounter with it and where to call if it accidentally comes across you on the street?

What is radioactivity and radiation?

Radioactivity- instability of the nuclei of some atoms, manifested in their ability to undergo spontaneous transformations (decay), accompanied by the emission of ionizing radiation or radiation. Further we will talk only about the radiation that is associated with radioactivity.

Radiation, or ionizing radiation- these are particles and gamma quanta, the energy of which is high enough to create ions of different signs when exposed to matter. Radiation cannot be caused by chemical reactions.

What kind of radiation is there?

There are several types of radiation.

Alpha particles: relatively heavy, positively charged particles that are helium nuclei.
Beta particles- they're just electrons.
Gamma radiation has the same electromagnetic nature as visible light, but has much greater penetrating power.
Neutrons- electrically neutral particles arise mainly directly near an operating nuclear reactor, where access, of course, is regulated.
X-ray radiation similar to gamma radiation, but has less energy. By the way, our Sun is one of the natural sources of X-ray radiation, but earth's atmosphere provides reliable protection against it.

Ultraviolet radiation And laser radiation in our consideration are not radiation.

Charged particles interact very strongly with matter, therefore, on the one hand, even one alpha particle, when entering a living organism, can destroy or damage many cells, but, on the other hand, for the same reason, sufficient protection from alpha and beta -radiation is any, even a very thin layer of solid or liquid substance - for example, ordinary clothing (if, of course, the radiation source is outside).

It is necessary to distinguish radioactivity And radiation. Sources of radiation - radioactive substances or nuclear technical installations (reactors, accelerators, X-ray equipment, etc.) - can exist for a considerable time, but radiation exists only until it is absorbed in any substance.

What can the effects of radiation on humans lead to?

The effect of radiation on humans is called exposure. The basis of this effect is the transfer of radiation energy to the cells of the body.
Irradiation may cause metabolic disorders, infectious complications, leukemia and malignant tumors, radiation infertility, radiation cataract, radiation burn, radiation sickness. The effects of radiation have a stronger effect on dividing cells, and therefore radiation is much more dangerous for children than for adults.

As for the frequently mentioned genetic(i.e., inherited) mutations as a consequence of human irradiation, such mutations have never been discovered. Even among the 78,000 children of Japanese survivors of the atomic bombings of Hiroshima and Nagasaki, no increase in the incidence of hereditary diseases was observed ( book “Life after Chernobyl” by Swedish scientists S. Kullander and B. Larson).

It should be remembered that much greater REAL damage to human health is caused by emissions from the chemical and steel industries, not to mention the fact that science does not yet know the mechanism of malignant degeneration of tissues from external influences.

How can radiation enter the body?

The human body reacts to radiation, not to its source.
Those sources of radiation, which are radioactive substances, can enter the body with food and water (through the intestines), through the lungs (during breathing) and, to a small extent, through the skin, as well as during medical radioisotope diagnostics. In this case we talk about internal training.
In addition, a person may be exposed to external radiation from a radiation source that is located outside his body.
Internal radiation is much more dangerous than external radiation.

Is radiation transmitted as a disease?

Radiation is created by radioactive substances or specially designed equipment. The radiation itself, when affecting the body, does not form radio in it. active substances, and does not turn it into a new source of radiation. Thus, a person does not become radioactive after an X-ray or fluorographic examination. By the way, an X-ray image (film) also does not contain radioactivity.

The exception is the situation in which the body is intentionally introduced radioactive drugs(for example, during radioisotope examination thyroid gland), and the person becomes a source of radiation for a short time. However, drugs of this kind are specially selected so that they quickly lose their radioactivity due to decay, and the intensity of the radiation quickly decreases.

Of course " get dirty» body or clothing exposed to radioactive liquid, powder or dust. Then some of this radioactive “dirt” - along with ordinary dirt - can be transferred upon contact to another person. Unlike a disease, which, transmitted from person to person, reproduces its harmful force (and can even lead to an epidemic), the transmission of dirt leads to its rapid dilution to safe limits.

In what units is radioactivity measured?

Measure radioactivity serves activity. Measured in Becquerelach (Bk), which corresponds to 1 decay per second. The activity content of a substance is often estimated per unit weight of the substance (Bq/kg) or volume (Bq/cubic meter).
There is also such a unit of activity as Curie (Ki). This is a huge amount: 1 Ci = 37000000000 (37*10^9) Bq.
The activity of a radioactive source characterizes its power. So, in the source of activity 1 Curie occurs 37000000000 decays per second.

As mentioned above, during these decays the source emits ionizing radiation. The measure of the ionization effect of this radiation on a substance is exposure dose. Often measured in X-rays (R). Since 1 Roentgen is a rather large value, in practice it is more convenient to use the millionth ( mkr) or thousandth ( mR) fractions of Roentgen.
Action of common household dosimeters is based on measuring ionization over a certain time, that is, the exposure dose rate. Unit of measurement of exposure dose rate - microRoentgen/hour .

The dose rate multiplied by time is called dose. Dose rate and dose are related in the same way as the speed of a car and the distance traveled by this car (path).
To assess the impact on the human body, concepts are used equivalent dose And equivalent dose rate. Measured accordingly in Sievertach (Sv) And Sieverts/hour (Sv/hour). In everyday life we can assume that 1 Sievert = 100 Roentgen. It is necessary to indicate which organ, part or entire body the dose was given to.

It can be shown that the above-mentioned point source with an activity of 1 Curie (for definiteness, we consider a cesium-137 source) at a distance of 1 meter from itself creates an exposure dose rate of approximately 0.3 Roentgen/hour, and at a distance of 10 meters - approximately 0.003 Roentgen/hour. Reducing dose rate with increasing distance always occurs from the source and is determined by the laws of radiation propagation.

Now the typical error of the funds is absolutely clear mass media, reporting: " Today, on such and such a street, a radioactive source of 10 thousand roentgens was discovered when the norm is 20».
Firstly, the dose is measured in Roentgens, and the source characteristic is its activity. A source of so many X-rays is the same as a bag of potatoes weighing so many minutes.
Therefore, in any case, we can only talk about the dose rate from the source. And not just the dose rate, but with an indication at what distance from the source this dose rate was measured.

Further, the following considerations can be made. 10 thousand roentgens/hour is quite a large value. It can hardly be measured with a dosimeter in hand, since when approaching the source, the dosimeter will first show both 100 Roentgen/hour and 1000 Roentgen/hour! It is very difficult to assume that the dosimetrist will continue to approach the source. Since dosimeters measure the dose rate in micro-Roentgen/hour, we can assume that in this case we are talking about 10 thousand micro-Roentgen/hour = 10 milli-Roentgen/hour = 0.01 Roentgen/hour. Such sources, although they do not pose a mortal danger, are less common on the street than hundred-ruble bills, and this can be a topic for an information message. Moreover, the mention of the “standard 20” can be understood as a conditional upper limit of the usual dosimeter readings in the city, i.e. 20 micro-Roentgen/hour.

Therefore, the correct message, apparently, should look like this: “Today, on such and such a street, a radioactive source was discovered, close to which the dosimeter shows 10 thousand micro-roentgens per hour, despite the fact that the average value of background radiation in our city does not exceed 20 micro-roentgens per hour "

What are isotopes?

There are more than 100 in the periodic table chemical elements. Almost each of them is represented by a mixture of stable and radioactive atoms which are called isotopes of this element. About 2000 isotopes are known, of which about 300 are stable.
For example, the first element of the periodic table - hydrogen - has the following isotopes:
hydrogen H-1 (stable)
deuterium N-2 (stable)
tritium N-3 (radioactive, half-life 12 years)

Radioactive isotopes are usually called radionuclides .

What is half-life?

The number of radioactive nuclei of the same type constantly decreases over time due to their decay.
The decay rate is usually characterized by a half-life: this is the time during which the number of radioactive nuclei of a certain type will decrease by 2 times.
Absolutely wrong is the following interpretation of the concept of “half-life”: “ if a radioactive substance has a half-life of 1 hour, this means that after 1 hour its first half will decay, and after another 1 hour the second half will decay, and this substance will completely disappear (disintegrate)«.

For a radionuclide with a half-life of 1 hour, this means that after 1 hour its amount will become 2 times less than the original, after 2 hours - 4 times, after 3 hours - 8 times, etc., but will never completely disappear. The radiation emitted by this substance will decrease in the same proportion. Therefore, it is possible to predict the radiation situation for the future if you know what and in what quantities of radioactive substances create radiation in a given place in this moment time.

Everyone has it radionuclide- mine half life, it can range from fractions of a second to billions of years. It is important that the half-life of a given radionuclide is constant, and it is impossible to change it.
Nuclei formed during radioactive decay, in turn, can also be radioactive. For example, radioactive radon-222 owes its origin to radioactive uranium-238.

Sometimes there are statements that radioactive waste in storage facilities will completely decay within 300 years. This is wrong. It’s just that this time will be approximately 10 half-lives of cesium-137, one of the most common man-made radionuclides, and over 300 years its radioactivity in waste will decrease almost 1000 times, but, unfortunately, will not disappear.

What is radioactive around us?

The following diagram will help to assess the impact on a person of certain sources of radiation (according to A.G. Zelenkov, 1990).

Based on its origin, radioactivity is divided into natural (natural) and man-made.

a) Natural radioactivity
Natural radioactivity has existed for billions of years and is literally everywhere. Ionizing radiation existed on Earth long before the origin of life on it and was present in space before the emergence of the Earth itself. Radioactive materials have been part of the Earth since its birth. Every person is slightly radioactive: in the tissues of the human body, one of the main sources of natural radiation is potassium-40 and rubidium-87, and there is no way to get rid of them.

Let's take into account that modern man spends up to 80% of his time indoors - at home or at work, where he receives the main dose of radiation: although buildings are protected from radiation from the outside, the building materials from which they are built contain natural radioactivity. Radon and its decay products make a significant contribution to human exposure.

b) Radon
The main source of this radioactive noble gas is the earth's crust. Penetrating through cracks and crevices in the foundation, floor and walls, radon lingers indoors. Another source of radon indoors is the building materials themselves (concrete, brick, etc.), which contain natural radionuclides that are a source of radon. Radon can also enter homes with water (especially if it is supplied from artesian wells), when burning natural gas, etc.
Radon is 7.5 times heavier than air. As a result, radon concentrations in the upper floors of multi-story buildings are usually lower than on the ground floor.
A person receives the bulk of the radiation dose from radon while in a closed, unventilated room; Regular ventilation can reduce radon concentrations several times.
With prolonged exposure to radon and its products in the human body, the risk of lung cancer increases many times over.
The following diagram will help you compare the emission power of different radon sources.

c) Technogenic radioactivity
Man-made radioactivity occurs due to human activity.
Conscious economic activity, during which the redistribution and concentration of natural radionuclides occurs, leads to noticeable changes in the natural radiation background. This includes the extraction and combustion of coal, oil, gas, and other fossil fuels, the use of phosphate fertilizers, and the extraction and processing of ores.
For example, studies of oil fields in Russia show a significant excess of permissible radioactivity standards, an increase in radiation levels in the area of wells caused by the deposition of radium-226, thorium-232 and potassium-40 salts on the equipment and adjacent soil. Operating and spent pipes are especially contaminated and often have to be classified as radioactive waste.
This type of transport civil Aviation, exposes its passengers to increased exposure to cosmic radiation.
And, of course, nuclear weapons testing, nuclear energy enterprises and industry make their contribution.

Of course, accidental (uncontrolled) spread of radioactive sources is also possible: accidents, losses, thefts, spraying, etc. Such situations, fortunately, are VERY RARE. Moreover, their danger should not be exaggerated.
For comparison, the contribution of Chernobyl to the total collective dose of radiation that Russians and Ukrainians living in contaminated areas will receive in the next 50 years will be only 2%, while 60% of the dose will be determined by natural radioactivity.

What do commonly found radioactive objects look like?

According to MosNPO Radon, more than 70 percent of all cases of radioactive contamination detected in Moscow occur in residential areas with intensive new construction and green areas of the capital. It was in the latter that, in the 50-60s, household waste dumps were located, where low-level radioactive industrial waste, which was then considered relatively safe, was also dumped.

In addition, individual objects shown below can be carriers of radioactivity:

	A switch with a glow-in-the-dark toggle switch, the tip of which is painted with a permanent light composition based on radium salts. Dose rate for point-blank measurements is about 2 milliRoentgen/hour

Is a computer a source of radiation?

The only part of the computer for which we can talk about radiation is the monitors on cathode ray tubes(CRT); This does not apply to displays of other types (liquid crystal, plasma, etc.).
Monitors, along with regular CRT televisions, can be considered a weak source of X-ray radiation originating from the inner surface of the glass of the CRT screen. However, due to the large thickness of this same glass, it also absorbs a significant part of the radiation. To date, no impact of X-ray radiation from CRT monitors on health has been discovered, however, all modern CRTs are produced with a conditionally safe level of X-ray radiation.

Currently, regarding monitors, Swedish national standards are generally accepted for all manufacturers "MPR II", "TCO-92", -95, -99. These standards, in particular, regulate electric and magnetic fields from monitors.
As for the term “low radiation”, this is not a standard, but just a declaration by the manufacturer that he has done something, known only to him, in order to reduce radiation. The less common term “low emission” has a similar meaning.

The standards in force in Russia are set out in the document “ Hygienic requirements to personal electronic computers and work organization" (SanPiN SanPiN 2.2.2/2.4.1340-03), the full text is located at the address, and a short excerpt about the permissible values of all types of radiation from video monitors is here.

When fulfilling orders for radiation monitoring of the offices of a number of organizations in Moscow, LRK-1 employees carried out a dosimetric examination of about 50 CRT monitors of different brands, with screen diagonal sizes from 14 to 21 inches. In all cases, the dose rate at a distance of 5 cm from the monitors did not exceed 30 µR/hour, i.e. with a threefold reserve fit into permissible norm(100 microR/hour).

What is normal background radiation?

There are populated areas on Earth with increased background radiation. These are, for example, the highland cities of Bogota, Lhasa, Quito, where the level of cosmic radiation is approximately 5 times higher than at sea level.

These are also sandy zones with a high concentration of minerals containing phosphates with an admixture of uranium and thorium - in India (Kerala state) and Brazil (Espirito Santo state). We can mention the area where the waters come out from high concentration radium in Iran (Romser). Although in some of these areas the absorbed dose rate is 1000 times higher than the average on the Earth's surface, population surveys have not revealed changes in the structure of morbidity and mortality.

In addition, even for a specific area there is no “normal background” as a constant characteristic; it cannot be obtained as a result of a small number of measurements.
In any place, even for undeveloped territories where “no human has set foot,” the radiation background changes from point to point, as well as at each specific point over time. These background fluctuations can be quite significant. In populated areas, additional factors of enterprise activity, transport operation, etc. are superimposed. For example, at airfields, thanks to the high-quality concrete pavement with granite crushed stone, the background is usually higher than in the surrounding area.

Measurements of radiation background in the city of Moscow allow us to indicate the TYPICAL value of the background on the street (open area) - 8 - 12 μR/hour, in room - 15 - 20 µR/hour.

What are the standards for radioactivity?

There are a lot of standards regarding radioactivity—literally everything is regulated. In all cases a distinction is made between the public and the staff, i.e. persons whose work involves radioactivity (nuclear power plant workers, nuclear industry workers, etc.). Outside of their production, personnel belong to the population. For staff and production premises their own standards are established.

Further we will talk only about the norms for the population - that part of them that is directly related to ordinary life activities, based on The federal law“On Radiation Safety of the Population” No. 3-FZ dated 05.12.96 and “Radiation Safety Standards (NRB-99). Sanitary rules SP 2.6.1.1292-03".

The main task of radiation monitoring (measurements of radiation or radioactivity) is to determine the compliance of the radiation parameters of the object under study (dose rate in the room, content of radionuclides in building materials, etc.) with established standards.

a) air, food and water
The content of both man-made and natural radioactive substances is standardized for inhaled air, water and food.
In addition to NRB-99, “Hygienic requirements for the quality and safety of food raw materials and food products(SanPiN 2.3.2.560-96).”

b) building materials
The content of radioactive substances from the uranium and thorium families, as well as potassium-40 (in accordance with NRB-99) is normalized.
Specific effective activity (Aeff) of natural radionuclides in building materials used for newly built residential and public buildings (class 1),
Aeff = АRa +1.31АTh + 0.085 Ak should not exceed 370 Bq/kg,
where АRa and АTh are the specific activities of radium-226 and thorium-232, which are in equilibrium with other members of the uranium and thorium families, Ak is the specific activity of K-40 (Bq/kg).
GOST 30108-94 “Construction materials and products. Determination of the specific effective activity of natural radionuclides" and GOST R 50801-95 "Wood raw materials, timber, semi-finished products and products from wood and wood materials. Permissible specific activity of radionuclides, sampling and methods for measuring specific activity of radionuclides.”
Note that according to GOST 30108-94, the value Aeff m is taken as the result of determining the specific effective activity in the controlled material and establishing the class of the material:
Aeff m = Aeff + DAeff, where DAeff is the error in determining Aeff.

c) premises
The total content of radon and thoron in indoor air is normalized:
for new buildings - no more than 100 Bq/m3, for those already in use - no more than 200 Bq/m3.
In the city of Moscow, MGSN 2.02-97 “Permissible levels of ionizing radiation and radon in building areas” is used.

d) medical diagnostics
There are no dose limits for patients, but there is a requirement for minimum sufficient exposure levels to obtain diagnostic information.

e) computer equipment
The exposure dose rate of X-ray radiation at a distance of 5 cm from any point on a video monitor or personal computer should not exceed 100 µR/hour. The standard is contained in the document “Hygienic requirements for personal electronic computers and organization of work” (SanPiN 2.2.2/2.4.1340-03).

How to protect yourself from radiation?

They are protected from the source of radiation by time, distance and substance.

Time- due to the fact that the shorter the time spent near the radiation source, the lower the radiation dose received from it.
Distance- due to the fact that radiation decreases with distance from the compact source (proportional to the square of the distance). If at a distance of 1 meter from the radiation source the dosimeter records 1000 µR/hour, then at a distance of 5 meters the readings will drop to approximately 40 µR/hour.
Substance— you must strive to have as much matter as possible between you and the source of radiation: the more of it and the denser it is, the more of the radiation it will absorb.

Concerning main source exposure indoors - radon and its decay products, then regular ventilation allows to significantly reduce their contribution to the dose load.
In addition, if we are talking about building or decorating your own home, which is likely to last for more than one generation, you should try to buy radiation-safe building materials - fortunately, their range is now extremely rich.

Does alcohol help against radiation?

Alcohol taken shortly before exposure can, to some extent, reduce the effects of exposure. However, its protective effect is inferior to modern anti-radiation drugs.

When to think about radiation?

Always think. But in everyday life, the likelihood of encountering a radiation source that poses an immediate threat to health is extremely low. For example, in Moscow and the region, less than 50 such cases are recorded per year, and in most cases - thanks to the constant systematic work of professional dosimetrists (employees of the MosNPO "Radon" and the Central State Sanitary and Epidemiological System of Moscow) in the places where radiation sources and local radioactive contamination are most likely to be detected (landfills , pits, scrap metal warehouses).
Nevertheless, it is in everyday life that sometimes one should remember about radioactivity. It's useful to do this:

when buying an apartment, house, land,
when planning construction and finishing works,
when choosing and purchasing building and finishing materials for an apartment or house
when choosing materials for landscaping the area around the house (soil of bulk lawns, bulk coverings for tennis courts, paving slabs and paving stones, etc.)

It should still be noted that radiation is far from the most important reason for constant concern. According to the scale of relative danger of various types of anthropogenic impact on humans developed in the USA, radiation is at 26 - place, and the first two places are occupied heavy metals And chemical toxicants.

The word “radiation” most often refers to ionizing radiation associated with radioactive decay. At the same time, a person experiences the effects of non-ionizing types of radiation: electromagnetic and ultraviolet.

The main sources of radiation are:

natural radioactive substances around and inside us - 73%;
medical procedures(fluoroscopy and others) - 13%;
cosmic radiation - 14%.

Of course, there are man-made sources of pollution resulting from major accidents. These are the most dangerous events for humanity, since, as in a nuclear explosion, iodine (J-131), cesium (Cs-137) and strontium (mainly Sr-90) can be released. Weapons-grade plutonium (Pu-241) and its decay products are no less dangerous.

Also, do not forget that over the past 40 years the Earth’s atmosphere has been very heavily polluted by radioactive products of atomic and hydrogen bombs. Of course, at the moment, radioactive fallout is only due to natural disasters, for example during volcanic eruptions. But, on the other hand, when a nuclear charge splits at the moment of explosion, the radioactive isotope carbon-14 is formed with a half-life of 5,730 years. The explosions changed the equilibrium content of carbon-14 in the atmosphere by 2.6%. Currently, the average effective equivalent dose rate due to explosion products is about 1 mrem/year, which is approximately 1% of the dose rate due to natural background radiation.

mos-rep.ru

Energy is another reason for the serious accumulation of radionuclides in the body of humans and animals. Stone coals, used to operate thermal power plants, contain naturally occurring radioactive elements such as potassium-40, uranium-238 and thorium-232. The annual dose in the area of coal-fired thermal power plants is 0.5–5 mrem/year. By the way, nuclear power plants are characterized by significantly lower emissions.

Almost all inhabitants of the Earth are exposed to medical procedures using sources of ionizing radiation. But it's more complex issue, which we will return to a little later.

In what units is radiation measured?

Various units are used to measure the amount of radiation energy. In medicine, the main one is the sievert - the effective equivalent dose received in one procedure by the entire body. It is in sieverts per unit time that the level of background radiation is measured. The becquerel serves as a unit of measurement for the radioactivity of water, soil, etc., per unit volume.

Other units of measurement can be found in the table.

Term	Units		Unit ratio	Definition
Term	In the SI system	In the old system	Unit ratio	Definition
Activity	Becquerel, Bk		1 Ci = 3.7 × 10 10 Bq	Number of radioactive decays per unit time
Dose rate	Sievert per hour, Sv/h	X-ray 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	The amount of ionizing radiation energy transferred to a specific object
Effective dose	Sievert, Sv		1 rem = 0.01 Sv	Radiation dose, taking into account different sensitivity of organs to radiation

Consequences of radiation

The effect of radiation on humans is called exposure. Its main manifestation is acute radiation sickness, which has varying degrees of severity. Radiation sickness can occur when exposed to a dose equal to 1 sievert. A dose of 0.2 sievert increases the risk of cancer, and a dose of 3 sievert threatens the life of the exposed person.

Radiation sickness manifests itself in the form of the following symptoms: loss of strength, diarrhea, nausea and vomiting; dry, hacking cough; cardiac dysfunction.

In addition, irradiation causes radiation burns. Very large doses lead to skin death, even damage to muscles and bones, which is much worse to treat than chemical or thermal burns. Along with burns, metabolic disorders, infectious complications, radiation infertility, and radiation cataracts may appear.

The effects of radiation can manifest themselves through long time- This is the so-called stochastic effect. It is expressed in the fact that among irradiated people the frequency of certain oncological diseases. It is also theoretically possible genetic effects, however, even among the 78 thousand children of Japanese who survived the atomic bombing of Hiroshima and Nagasaki, no increase in the number of cases of hereditary diseases was found. This is despite the fact that the effects of radiation have a stronger effect on dividing cells, so radiation is much more dangerous for children than for adults.

Short-term, low-dose irradiation, used for examinations and treatment of certain diseases, produces an interesting effect called hormesis. This is stimulation of any body system external influences, having strength insufficient to manifest harmful factors. This effect allows the body to mobilize strength.

Statistically, radiation can increase the incidence of cancer, but it is very difficult to identify the direct effect of radiation, separating it from the effect of chemicals harmful substances, viruses and other things. It is known that after the bombing of Hiroshima, the first effects in the form of increased incidence began to appear only after 10 years or more. Cancer of the thyroid gland, breast and certain parts is directly associated with radiation.

chornobyl.in.ua

Natural background radiation is about 0.1–0.2 μSv/h. It is believed that a constant background level above 1.2 μSv/h is dangerous for humans (it is necessary to distinguish between the instantly absorbed radiation dose and the constant background dose). Is this too much? For comparison: the radiation level at a distance of 20 km from the Japanese nuclear power plant Fukushima-1 at the time of the accident exceeded the norm by 1,600 times. The maximum recorded radiation level at this distance is 161 μSv/h. After the explosion, radiation levels reached several thousand microsieverts per hour.

During a 2–3-hour flight over an ecologically clean area, a person receives radiation exposure of 20–30 μSv. The same radiation dose threatens if a person takes 10–15 pictures in one day using a modern X-ray apparatus - a visiograph. A couple of hours in front of a cathode ray monitor or TV gives the same radiation dose as one such photo. The annual dose from smoking one cigarette per day is 2.7 mSv. One fluorography - 0.6 mSv, one radiography - 1.3 mSv, one fluoroscopy - 5 mSv. Radiation from concrete walls is up to 3 mSv per year.

When irradiating the whole body and for the first group of critical organs (heart, lungs, brain, pancreas and others), regulatory documents establish a maximum dose of 50,000 μSv (5 rem) per year.

Acute radiation sickness develops with a single radiation dose of 1,000,000 μSv (25,000 digital fluorographs, 1,000 spinal x-rays in one day). Large doses have an even stronger effect:

750,000 μSv - short-term minor change in blood composition;
1,000,000 μSv - mild degree of radiation sickness;
4,500,000 μSv - severe radiation sickness (50% of those exposed die);
about 7,000,000 μSv - death.

Are x-ray examinations dangerous?

Most often we encounter radiation during medical research. However, the doses we receive in the process are so small that there is no need to be afraid of them. The exposure time of an old X-ray machine is 0.5–1.2 seconds. And with a modern visiograph everything happens 10 times faster: in 0.05–0.3 seconds.

According to the medical requirements set out in SanPiN 2.6.1.1192-03, when carrying out preventive medical x-ray procedures, the radiation dose should not exceed 1,000 µSv per year. How much is it in pictures? Quite a bit of:

500 targeted images (2–3 μSv) obtained using a radiovisiograph;
100 of the same images, but using good X-ray film (10–15 μSv);
80 digital orthopantomograms (13–17 μSv);
40 film orthopantomograms (25–30 μSv);
20 computed tomograms (45–60 μSv).

That is, if every day for the whole year we take one picture on a visiograph, add to this a couple of computed tomograms and the same number of orthopantomograms, then even in this case we will not go beyond the permitted doses.

Who should not be irradiated

However, there are people for whom even such types of radiation are strictly prohibited. According to the standards approved in Russia (SanPiN 2.6.1.1192-03), irradiation in the form of X-rays can be carried out only in the second half of pregnancy, with the exception of cases when the issue of abortion or the need for emergency or urgent care must be resolved.

Paragraph 7.18 of the document states: “X-ray examinations of pregnant women are carried out using all possible means and methods of protection so that the dose received by the fetus does not exceed 1 mSv for two months of undetected pregnancy. If the fetus receives a dose exceeding 100 mSv, the doctor is obliged to warn the patient about the possible consequences and recommend terminating the pregnancy.”

Young people who will become parents in the future need to protect their abdominal area and genitals from radiation. X-ray radiation has the most negative effect on blood cells and germ cells. In children, in general, the entire body should be shielded, except for the area being examined, and studies should be carried out only if necessary and as prescribed by a doctor.
Sergei Nelyubin, Head of the Department of X-ray Diagnostics, Russian Scientific Center for Surgery named after. B.V. Petrovsky, Candidate of Medical Sciences, Associate Professor

How to protect yourself

There are three main methods of protection against X-ray radiation: protection by time, protection by distance and shielding. That is, the less you are in the area of X-rays and the further you are from the radiation source, the lower the radiation dose.

Although safe dose The radiation exposure is designed for a year; however, you should not do several X-ray examinations on the same day, for example fluorography and. Well, every patient must have a radiation passport (it is included in medical card): in it the radiologist enters information about the dose received during each examination.

X-ray primarily affects the glands internal secretion, lungs. The same applies to small doses of radiation during accidents and releases of active substances. Therefore, doctors recommend breathing exercises as a preventative measure. They will help cleanse the lungs and activate the body's reserves.

To normalize the internal processes of the body and remove harmful substances, it is worth consuming more antioxidants: vitamins A, C, E (red wine, grapes). Sour cream, cottage cheese, milk, grain bread, bran, unprocessed rice, prunes are useful.

If food products cause certain concerns, you can use recommendations for residents of regions affected by the Chernobyl nuclear power plant accident.

»
In case of actual exposure due to an accident or in a contaminated area, quite a lot needs to be done. First you need to carry out decontamination: quickly and carefully remove clothes and shoes with radiation carriers, properly dispose of them, or at least remove radioactive dust from your belongings and surrounding surfaces. It is enough to wash your body and clothes (separately) under running water using detergents.

Before or after exposure to radiation, dietary supplements and anti-radiation medications are used. The best known medications are those containing a high content of iodine, which helps to effectively combat the negative effects of its radioactive isotope, which is localized in thyroid gland. To block the accumulation of radioactive cesium and prevent secondary damage, “Potassium orotate” is used. Calcium supplements deactivate the radioactive drug strontium by 90%. Dimethyl sulfide is indicated to protect cellular structures.

By the way, everyone knows Activated carbon can neutralize the effects of radiation. And the benefits of drinking vodka immediately after irradiation are not a myth at all. This really helps to remove radioactive isotopes from the body in the simplest cases.

Just don't forget: self-treatment should be carried out only if it is impossible to consult a doctor in a timely manner and only in the case of real and not fictitious exposure. X-ray diagnostics, watching TV or flying on an airplane do not affect the health of the average inhabitant of the Earth.

1. What is radioactivity and radiation?

The phenomenon of radioactivity was discovered in 1896 by the French scientist Henri Becquerel. Currently, it is widely used in science, technology, medicine, and industry. Radioactive elements natural origin present everywhere in surrounding a person environment. Artificial radionuclides are produced in large quantities, mainly as a by-product in the defense industry and nuclear power plants. When they enter the environment, they affect living organisms, which is where their danger lies. To correctly assess this danger, it is necessary to have a clear understanding of the scale of environmental pollution, the benefits brought by production, the main or by-product of which are radionuclides, and the losses associated with the abandonment of these productions, the real mechanisms of action of radiation, the consequences and existing protective measures .

Radioactivity- instability of the nuclei of some atoms, manifested in their ability to spontaneous transformations (decay), accompanied by the emission of ionizing radiation or radiation

2. What kind of radiation is there?

There are several types of radiation.
Alpha particles: relatively heavy, positively charged particles that are helium nuclei.
Beta particles- it's just electrons.
Gamma radiation has the same electromagnetic nature as visible light, but has much greater penetrating power. 2 Neutrons- electrically neutral particles arise mainly directly near an operating nuclear reactor, where access, of course, is regulated.
X-ray radiation similar to gamma radiation, but has less energy. By the way, our Sun is one of the natural sources of X-ray radiation, but the earth’s atmosphere provides reliable protection from it.

It is necessary to distinguish between radioactivity and radiation. Sources of radiation- radioactive substances or nuclear technical installations (reactors, accelerators, X-ray equipment, etc.) - can exist for a considerable time, and radiation exists only until it is absorbed in any substance.

3. What can the effects of radiation on humans lead to?

The effect of radiation on humans is called irradiation. The basis of this effect is the transfer of radiation energy to the cells of the body.
Radiation can cause metabolic disorders, infectious complications, leukemia and malignant tumors, radiation infertility, radiation cataracts, radiation burns, and radiation sickness.
The effects of radiation have a greater impact on dividing cells, and therefore radiation is much more dangerous for children than for adults.

4. How can radiation enter the body?

The human body reacts to radiation, not to its source. 3
Those sources of radiation, which are radioactive substances, can enter the body with food and water (through the intestines), through the lungs (during breathing) and, to a small extent, through the skin, as well as during medical radioisotope diagnostics. In this case they talk about internal radiation .
In addition, a person may be exposed to external radiation from a radiation source that is located outside his body.
Internal radiation is much more dangerous than external radiation. 5. Is radiation transmitted as a disease? Radiation is created by radioactive substances or specially designed equipment. The radiation itself, acting on the body, does not form radioactive substances in it, and does not turn it into a new source of radiation. Thus, a person does not become radioactive after an X-ray or fluorographic examination. By the way, an X-ray image (film) also does not contain radioactivity.

An exception is the situation in which radioactive drugs are deliberately introduced into the body (for example, during a radioisotope examination of the thyroid gland), and the person becomes a source of radiation for a short time. However, drugs of this kind are specially selected so that they quickly lose their radioactivity due to decay, and the intensity of the radiation quickly decreases.

6. In what units is radioactivity measured?

A measure of radioactivity is activity. It is measured in Becquerels (Bq), which corresponds to 1 decay per second. The activity content of a substance is often estimated per unit weight of the substance (Bq/kg) or volume (Bq/cubic meter).
There is also another unit of activity called the Curie (Ci). This is a huge value: 1 Ci = 37000000000 Bq.
The activity of a radioactive source characterizes its power. Thus, in a source with an activity of 1 Curie, 37000000000 decays occur per second.
4
As mentioned above, during these decays the source emits ionizing radiation. The measure of the ionization effect of this radiation on a substance is exposure dose. Often measured in Roentgens (R). Since 1 Roentgen is a fairly large value, in practice it is more convenient to use parts per million (μR) or thousandths (mR) of a Roentgen.
The operation of common household dosimeters is based on measuring ionization over a certain time, that is exposure dose rate. The unit of measurement for exposure dose rate is micro-Roentgen/hour.
The dose rate multiplied by time is called dose. Dose rate and dose are related in the same way as the speed of a car and the distance traveled by this car (path).
To assess the impact on the human body, concepts are used equivalent dose And equivalent dose rate. They are measured in Sieverts (Sv) and Sieverts/hour, respectively. In everyday life, we can assume that 1 Sievert = 100 Roentgen. It is necessary to indicate which organ, part or entire body the dose was given to.
It can be shown that the above-mentioned point source with an activity of 1 Curie (for definiteness, we consider a cesium-137 source) at a distance of 1 meter from itself creates an exposure dose rate of approximately 0.3 Roentgen/hour, and at a distance of 10 meters - approximately 0.003 Roentgen/hour. A decrease in dose rate with increasing distance from the source always occurs and is determined by the laws of radiation propagation.

7. What are isotopes?

There are more than 100 chemical elements in the periodic table. Almost each of them is represented by a mixture of stable and radioactive atoms, which are called isotopes of this element. About 2000 isotopes are known, of which about 300 are stable.
For example, the first element of the periodic table - hydrogen - has the following isotopes:
- hydrogen H-1 (stable),
- deuterium N-2 (stable),
- tritium H-3 (radioactive, half-life 12 years).

Radioactive isotopes are usually called radionuclides 5

8. What is half-life?

The number of radioactive nuclei of the same type constantly decreases over time due to their decay.
The decay rate is usually characterized half-life: this is the time during which the number of radioactive nuclei of a certain type will decrease by 2 times.
Absolutely wrong is the following interpretation of the concept of “half-life”: “if a radioactive substance has a half-life of 1 hour, this means that after 1 hour its first half will decay, and after another 1 hour the second half will decay, and this substance will completely disappear (disintegrate).”

Each radionuclide has its own half-life; it can range from fractions of a second to billions of years. It is important that the half-life of a given radionuclide is constant and cannot be changed.
Nuclei formed during radioactive decay, in turn, can also be radioactive. For example, radioactive radon-222 owes its origin to radioactive uranium-238.

9. What is radioactive around us?
6

The following diagram will help to assess the impact on a person of certain sources of radiation (according to A.G. Zelenkov, 1990).

Radiation and ionizing radiation

The word “radiation” comes from the Latin word “radiatio”, which means “radiance”, “radiation”.

The main meaning of the word “radiation” (in accordance with Ozhegov’s dictionary, published in 1953): radiation coming from some body. However, over time it was replaced by one of its narrower meanings - radioactive or ionizing radiation.

Radon actively enters our homes with household gas, tap water (especially if it is extracted from very deep wells), or it simply seeps through microcracks in the soil, accumulating in basements and on the lower floors. Reducing the radon content, unlike other sources of radiation, is very simple: just regularly ventilate the room and the concentration of the dangerous gas will decrease several times.

Artificial radioactivity

Unlike natural sources of radiation, artificial radioactivity arose and is spread exclusively by human forces. The main man-made radioactive sources include nuclear weapons, industrial waste, nuclear power plants, medical equipment, antiquities taken from “forbidden” zones after the Chernobyl nuclear power plant accident, and some precious stones.

Radiation can enter our body in any way, often the culprit is objects that do not cause any suspicion in us. The best way to protect yourself - check your home and the objects in it for the level of radioactivity or buy a radiation dosimeter. We are responsible for our own life and health. Protect yourself from radiation!

In the Russian Federation there are standards regulating permissible levels of ionizing radiation. From August 15, 2010 to the present, sanitary and epidemiological rules and regulations SanPiN 2.1.2.2645-10 “Sanitary and epidemiological requirements for living conditions in residential buildings and premises” have been in force.

Last changes were introduced on December 15, 2010 - SanPiN 2.1.2.2801-10 “Changes and additions No. 1 to SanPiN 2.1.2.2645-10 “Sanitary and epidemiological requirements for living conditions in residential buildings and premises”.

The following regulations regarding ionizing radiation also apply:

In accordance with the current SanPiN, “the effective dose rate of gamma radiation inside buildings should not exceed the dose rate in open areas by more than 0.2 μSv/hour.” It does not say what the permissible dose rate is in open areas! SanPiN 2.6.1.2523-09 states that “ permissible value effective dose, caused by the total impact natural radiation sources, for the population not installed. Reducing public exposure is achieved by establishing a system of restrictions on public exposure from individual natural radiation sources,” but at the same time, when designing new residential and public buildings, it must be ensured that the average annual equivalent equilibrium volumetric activity of daughter isotopes of radon and thoron in indoor air does not exceed 100 Bq/m3, and in operating buildings the average annual equivalent equilibrium volumetric activity of the daughter products of radon and thoron in the air of residential premises should not exceed 200 Bq/m3.

However, SanPiN 2.6.1.2523-09 in Table 3.1 states that the limit of the effective radiation dose for the population is 1 mSv per year on average for any consecutive 5 years, but no more than 5 mSv per year. Thus, it can be calculated that maximum effective dose rate is equal to 5 mSv divided by 8760 hours (the number of hours in a year), which is equal to 0.57 μSv/hour.

Radiation plays a huge role in the development of civilization at this historical stage. Thanks to the phenomenon of radioactivity, significant breakthroughs have been made in the field of medicine and in various industries, including energy. But at the same time, the negative aspects of the properties of radioactive elements began to appear more and more clearly: it turned out that the effects of radiation on the body can have tragic consequences. Such a fact could not escape the attention of the public. And the more we learned about the effects of radiation on human body and the environment, the more controversial opinions became about how large a role radiation should play in various spheres of human activity. Unfortunately, the lack of reliable information causes an inadequate perception of this problem. Newspaper stories about six-legged lambs and two-headed babies are causing widespread panic. The problem of radiation pollution has become one of the most pressing. Therefore, it is necessary to clarify the situation and find the right approach. Radioactivity should be considered as an integral part of our life, but without knowledge of the patterns of processes associated with radiation, it is impossible to really assess the situation.

For this purpose special international organizations, dealing with radiation problems, including the International Commission on Radiation Protection (ICRP), which has existed since the late 1920s, as well as the Scientific Committee on the Effects of Atomic Radiation (SCEAR), created in 1955 within the UN. In this work, the author made extensive use of the data presented in the brochure “Radiation. Doses, effects, risk”, prepared on the basis of the committee’s research materials.

Radiation has always existed. Radioactive elements have been part of the Earth since the beginning of its existence and continue to be present to the present day. However, the phenomenon of radioactivity itself was discovered only a hundred years ago.

In 1896, the French scientist Henri Becquerel accidentally discovered that after prolonged contact with a piece of mineral containing uranium, traces of radiation appeared on photographic plates after development.

Later, Marie Curie (the author of the term “radioactivity”) and her husband Pierre Curie became interested in this phenomenon. In 1898, they discovered that radiation transforms uranium into other elements, which the young scientists named polonium and radium. Unfortunately, people who deal with radiation professionally have put their health and even their lives in danger due to frequent contact with radioactive substances. Despite this, research continued, and as a result, humanity has very reliable information about the process of reactions in radioactive masses, which are largely determined by the structural features and properties of the atom.

It is known that the atom contains three types of elements: negatively charged electrons move in orbits around the nucleus - tightly coupled positively charged protons and electrically neutral neutrons. Chemical elements are distinguished by the number of protons. The same number of protons and electrons determines the electrical neutrality of the atom. The number of neutrons can vary, and the stability of the isotopes changes depending on this.

Most nuclides (the nuclei of all isotopes of chemical elements) are unstable and constantly transform into other nuclides. The chain of transformations is accompanied by radiation: in a simplified form, the emission of two protons and two neutrons ((-particles) by the nucleus is called alpha radiation, the emission of an electron is called beta radiation, and both of these processes occur with the release of energy. Sometimes an additional release of pure energy occurs, called gamma radiation.

Radioactive decay is the entire process of spontaneous decay of an unstable nuclide. Radionuclide is an unstable nuclide capable of spontaneous decay. The half-life of an isotope is the time during which, on average, half of all radionuclides of a given type in any radioactive source decay. Radiation activity of a sample is the number of decays per second in a given radioactive sample; unit of measurement - becquerel (Bq) “Absorbed dose* - the energy of ionizing radiation absorbed by the irradiated body (body tissues), calculated per unit mass. Equivalent dose** - absorbed dose, multiplied by a coefficient reflecting the ability of this type of radiation to damage body tissues. Effective equivalent dose*** - equivalent dose multiplied by a coefficient that takes into account the different sensitivity of different tissues to radiation. Collective effective equivalent dose**** is the effective equivalent dose received by a group of people from any radiation source. The total collective effective equivalent dose is the collective effective equivalent dose that generations of people will receive from any source over the entire period of its continued existence” (“Radiation...”, p. 13)

The effects of radiation on the body can vary, but they are almost always negative. In small doses, radiation can become a catalyst for processes leading to cancer or genetic disorders, and in large doses it often leads to complete or partial death of the body due to the destruction of tissue cells.

* unit of measurement in the SI system - gray (Gy)
** unit of measurement in the SI system - sievert (Sv)
*** unit of measurement in the SI system - sievert (Sv)
****unit of measurement in the SI system - man-sievert (man-Sv)

The difficulty in tracking the sequence of events caused by radiation is that the effects of radiation, especially at low doses, may not be immediately apparent and often take years or even decades for the disease to develop. In addition, due to the different penetrating ability different types Radioactive radiation has different effects on the body: alpha particles are the most dangerous, but for alpha radiation even a sheet of paper is an insurmountable barrier; beta radiation can pass into body tissue to a depth of one to two centimeters; the most harmless gamma radiation is characterized by the greatest penetrating ability: it can only be stopped by a thick slab of materials with a high absorption coefficient, for example, concrete or lead. The sensitivity of individual organs to radioactive radiation also varies. Therefore, in order to obtain the most reliable information about the degree of risk, it is necessary to take into account the corresponding tissue sensitivity coefficients when calculating the equivalent radiation dose:

0.03 - bone tissue
0.03 - thyroid gland
0.12 - red bone marrow
0.12 - light
0.15 - mammary gland
0.25 - ovaries or testes
0.30 - other fabrics
1.00 - the body as a whole.

The likelihood of tissue damage depends on the total dose and the dosage size, since, thanks to their repair abilities, most organs have the ability to recover after a series of small doses.

However, there are doses at which death is almost inevitable. For example, doses of the order of 100 Gy lead to death after a few days or even hours due to damage to the central nervous system, from hemorrhage as a result of a radiation dose of 10-50 Gy, death occurs in one to two weeks, and a dose of 3-5 Gy threatens to be fatal for approximately half of those exposed. Knowledge of the body’s specific response to certain doses is necessary to assess the consequences of high doses of radiation during accidents of nuclear installations and devices or the danger of exposure during prolonged stay in areas of increased radiation, both from natural sources and in the case of radioactive contamination.

The most common and serious damage caused by radiation, namely cancer and genetic disorders, should be examined in more detail.

In the case of cancer, it is difficult to estimate the likelihood of disease as a consequence of radiation. Any, even the smallest dose, can lead to irreversible consequences, but this is not predetermined. However, it has been established that the likelihood of disease increases in direct proportion to the radiation dose. Among the most common cancers caused by radiation are leukemia. Estimates of the probability of death from leukemia are more reliable than those for other types of cancer. This can be explained by the fact that leukemia is the first to manifest itself, causing death on average 10 years after the moment of irradiation. Leukemias are followed “in popularity” by: breast cancer, thyroid cancer and lung cancer. The stomach, liver, intestines and other organs and tissues are less sensitive. The impact of radiological radiation is sharply enhanced by other unfavorable environmental factors (the phenomenon of synergy). Thus, the mortality rate from radiation in smokers is noticeably higher.

As for the genetic consequences of radiation, they manifest themselves in the form of chromosomal aberrations (including changes in the number or structure of chromosomes) and gene mutations. Gene mutations appear immediately in the first generation (dominant mutations) or only if both parents have the same gene mutated (recessive mutations), which is unlikely. Studying the genetic effects of radiation is even more difficult than in the case of cancer. It is not known what genetic damage is caused by irradiation; it can manifest itself over many generations; it is impossible to distinguish it from those caused by other causes. It is necessary to evaluate the occurrence of hereditary defects in humans based on the results of animal experiments.

When assessing risk, SCEAR uses two approaches: one determines the immediate effect of a given dose, and the other determines the dose at which the frequency of occurrence of offspring with a particular anomaly doubles compared to normal radiation conditions.

Thus, with the first approach, it was established that a dose of 1 Gy received at a low radiation background by male individuals (for women, estimates are less certain) causes the appearance of from 1000 to 2000 mutations leading to serious consequences, and from 30 to 1000 chromosomal aberrations for every million live births. With the second approach we obtained following results: Chronic exposure at a dose rate of 1 Gy per generation will result in about 2000 serious genetic diseases for every million live newborns among children of those who were exposed to such radiation.

These estimates are unreliable, but necessary. The genetic consequences of radiation are expressed in such quantitative parameters as a reduction in life expectancy and period of disability, although it is recognized that these estimates are no more than a first rough estimate. Thus, chronic irradiation of the population with a dose rate of 1 Gy per generation reduces the period of working capacity by 50,000 years, and life expectancy by 50,000 years for every million living newborns among children of the first irradiated generation; with constant irradiation of many generations, the following estimates are obtained: 340,000 years and 286,000 years, respectively.

Now that we have an understanding of the effects of radiation exposure on living tissue, we need to find out in what situations we are most susceptible to this effect.

There are two methods of irradiation: if radioactive substances are outside the body and irradiate it from the outside, then we are talking about external irradiation. Another method of irradiation - when radionuclides enter the body with air, food and water - is called internal. Sources of radioactive radiation are very diverse, but they can be combined into two large groups: natural and artificial (man-made). Moreover, the main share of radiation (more than 75% of the annual effective equivalent dose) falls on the natural background.

Natural sources of radiation. Natural radionuclides are divided into four groups: long-lived (uranium-238, uranium-235, thorium-232); short-lived (radium, radon); long-lived solitary, not forming families (potassium-40); radionuclides resulting from the interaction of cosmic particles with atomic nuclei Earth substances (carbon-14).

Various types of radiation reach the Earth's surface either from space or from radioactive substances in the Earth's crust, with terrestrial sources responsible on average for 5/6 of the annual effective dose equivalent received by the population, mainly due to internal exposure. Radiation levels are not the same for various areas. Thus, the North and South Poles are more susceptible to influence than the equatorial zone. cosmic rays due to the presence of a magnetic field near the Earth, which deflects charged radioactive particles. In addition, the greater the distance from the earth's surface, the more intense the cosmic radiation. In other words, living in mountainous areas and constantly using air transport, we are exposed to an additional risk of exposure. People living above 2000 m above sea level receive, on average, an effective equivalent dose from cosmic rays several times greater than those living at sea level. When rising from a height of 4000 m (the maximum altitude for human habitation) to 12,000 m (the maximum flight altitude of passenger air transport), the level of exposure increases by 25 times. The approximate dose for the flight New York - Paris according to UNSCEAR in 1985 was 50 microsieverts for 7.5 hours of flight. In total, through the use of air transport, the Earth's population received an effective equivalent dose of about 2000 man-Sv per year. Levels of terrestrial radiation are also distributed unevenly over the Earth's surface and depend on the composition and concentration of radioactive substances in the earth's crust. The so-called anomalous radiation fields of natural origin are formed in the case of the enrichment of certain types of rocks with uranium, thorium, at deposits of radioactive elements in various rocks, with the modern introduction of uranium, radium, radon into surface and The groundwater, geological environment. According to studies conducted in France, Germany, Italy, Japan and the USA, about 95% of the population of these countries live in areas where the radiation dose rate ranges on average from 0.3 to 0.6 millisieverts per year. These data can be taken as global averages, since the natural conditions in the above countries are different.

There are, however, a few "hot spots" where radiation levels are much higher. These include several areas in Brazil: the area around Poços de Caldas and the beaches near Guarapari, a city of 12,000 people where approximately 30,000 holidaymakers come annually to relax, where radiation levels reach 250 and 175 millisieverts per year, respectively. This exceeds the average by 500-800 times. Here, as well as in another part of the world, on the southwestern coast of India, a similar phenomenon is due to increased content thorium in the sands. The above areas in Brazil and India are the most studied in this aspect, but there are many other places with high level radiation, for example in France, Nigeria, Madagascar.

Throughout Russia, zones of increased radioactivity are also unevenly distributed and are known both in the European part of the country and in the Trans-Urals, Polar Urals, Western Siberia, Baikal region, in the Far East, Kamchatka, Northeast. Among natural radionuclides, the largest contribution (more than 50%) to the total radiation dose is made by radon and its daughter decay products (including radium). The danger of radon lies in its wide distribution, high penetrating ability and migration mobility (activity), decay with the formation of radium and other highly active radionuclides. The half-life of radon is relatively short and amounts to 3.823 days. Radon is difficult to identify without the use of special instruments, since it has no color or odor. One of the most important aspects of the radon problem is internal radon exposure: the products formed during its decay in the form of tiny particles penetrate the respiratory system, and their existence in the body is accompanied by alpha radiation. Both in Russia and in the West, a lot of attention is paid to the radon problem, since as a result of studies it was found that in most cases the content of radon in the air indoors and in tap water exceeds the maximum permissible concentration. Thus, the highest concentration of radon and its decay products recorded in our country corresponds to an irradiation dose of 3000-4000 rem per year, which exceeds the MPC by two to three orders of magnitude. Information obtained in recent decades shows that in Russian Federation Radon is also widespread in the surface layer of the atmosphere, subsurface air and groundwater.

In Russia, the problem of radon is still poorly studied, but it is reliably known that in some regions its concentration is especially high. These include the so-called radon “spot”, covering lakes Onega, Ladoga and the Gulf of Finland, a wide zone extending from the Middle Urals to the west, the southern part of the Western Urals, the Polar Urals, the Yenisei Ridge, the Western Baikal region, the Amur region, the north of the Khabarovsk Territory , Chukotka Peninsula (“Ecology,...”, 263).

Sources of radiation created by man (man-made)

Artificial sources of radiation exposure differ significantly from natural ones not only in their origin. First, individual doses received vary greatly different people from artificial radionuclides. In most cases, these doses are small, but sometimes exposure from man-made sources is much more intense than from natural sources. Secondly, for technogenic sources the mentioned variability is much more pronounced than for natural ones. Finally, pollution from man-made radiation sources (other than fallout from nuclear explosions) is easier to control than naturally occurring pollution. Atomic energy is used by humans for various purposes: in medicine, to produce energy and detect fires, to make luminous watch dials, to search for minerals and, finally, to create atomic weapons. The main contribution to pollution from artificial sources comes from various medical procedures and treatments involving the use of radioactivity. The main device that no large clinic can do without is an X-ray machine, but there are many other diagnostic and treatment methods associated with the use of radioisotopes. The exact number of people undergoing such examinations and treatment and the doses they receive are unknown, but it can be argued that for many countries the use of the phenomenon of radioactivity in medicine remains almost the only man-made source of radiation. In principle, radiation in medicine is not so dangerous if it is not abused. But, unfortunately, unreasonably large doses are often applied to the patient. Among the methods that help reduce risk are reducing the area of the X-ray beam, its filtration, which removes excess radiation, proper shielding and the most banal thing, namely the serviceability of the equipment and its proper operation. Due to the lack of more complete data, UNSCEAR was forced to accept overall assessment annual collective effective equivalent dose, according to at least, from x-ray examinations to developed countries based on data submitted to the committee by Poland and Japan by 1985, a value of 1000 man-Sv per 1 million inhabitants. Most likely, for developing countries this value will be lower, but individual doses may be higher. It has also been calculated that the collective effective equivalent dose from radiation in medical purposes in general (including the use of radiation therapy to treat cancer) for the entire world population is approximately 1,600,000 man-Sv per year. The next source of radiation created by human hands is radioactive fallout that fell as a result of testing nuclear weapons in the atmosphere, and, despite the fact that the bulk of the explosions were carried out back in the 1950-60s, we are still experiencing their consequences. As a result of the explosion, some of the radioactive substances fall out near the test site, some are retained in the troposphere and then, over the course of a month, are transported by the wind over long distances, gradually settling on the ground, while remaining at approximately the same latitude. However, a large proportion of radioactive material is released into the stratosphere and remains there for a longer time, also dispersing over the earth's surface. Radioactive fallout contains a large number of different radionuclides, but the most important of them are zirconium-95, cesium-137, strontium-90 and carbon-14, whose half-lives are respectively 64 days, 30 years (cesium and strontium) and 5730 years. According to UNSCEAR, the expected total collective effective equivalent dose from all nuclear explosions carried out by 1985 was 30,000,000 man-Sv. By 1980, the world's population received only 12% of this dose, and the rest is still receiving and will continue to receive for millions of years. One of the most discussed sources of radiation today is nuclear energy. In fact, when normal operation nuclear installations, the damage from them is insignificant. The fact is that the process of producing energy from nuclear fuel is complex and takes place in several stages. The nuclear fuel cycle begins with the mining and enrichment of uranium ore, then the nuclear fuel itself is produced, and after the fuel has been processed at a nuclear power plant, it is sometimes possible to reuse it through the extraction of uranium and plutonium from it. The final stage of the cycle is, as a rule, the disposal of radioactive waste.

At each stage, radioactive substances are released into the environment, and their volume can vary greatly depending on the design of the reactor and other conditions. In addition, a serious problem is the disposal of radioactive waste, which will continue to serve as a source of pollution for thousands and millions of years.

Radiation doses vary depending on time and distance. The further a person lives from the station, the lower the dose he receives.

Among the products of nuclear power plants, tritium poses the greatest danger. Due to its ability to dissolve well in water and evaporate intensively, tritium accumulates in the water used in the energy production process and then enters the cooler reservoir, and, accordingly, into nearby drainage reservoirs, groundwater, and the ground layer of the atmosphere. Its half-life is 3.82 days. Its decay is accompanied by alpha radiation. Increased concentrations of this radioisotope have been recorded in the natural environments of many nuclear power plants. So far we have been talking about normal work nuclear power plants, but using the example of the Chernobyl tragedy, we can draw a conclusion about the extremely great potential danger of nuclear energy: with any minimal failure of a nuclear power plant, especially a large one, it can have an irreparable impact on the entire ecosystem of the Earth.

The scale of the Chernobyl accident could not but arouse keen interest from the public. But few people realize the number of minor problems in the operation of nuclear power plants in different countries peace.

Thus, the article by M. Pronin, prepared based on materials from the domestic and foreign press in 1992, contains the following data:

“...From 1971 to 1984. There were 151 accidents at nuclear power plants in Germany. In Japan, there were 37 operating nuclear power plants from 1981 to 1985. 390 accidents were registered, 69% of which were accompanied by the leakage of radioactive substances... In 1985, 3,000 system malfunctions and 764 temporary shutdowns of nuclear power plants were recorded in the USA...", etc. In addition, the author of the article points to the relevance, at least in 1992, of the problem of deliberate destruction of enterprises in the nuclear fuel energy cycle, which is associated with the unfavorable political situation in a number of regions. We can only hope for the future consciousness of those who “digging under themselves” in this way. It remains to indicate several artificial sources of radiation pollution that each of us encounters on a daily basis. These are, first of all, building materials that are characterized by increased radioactivity. Among such materials are some varieties of granites, pumice and concrete, in the production of which alumina, phosphogypsum and calcium silicate slag were used. There are known cases when building materials were produced from nuclear energy waste, which is contrary to all standards. Natural radiation of terrestrial origin is added to the radiation emanating from the building itself. The simplest and most affordable way to at least partially protect yourself from radiation at home or at work is to ventilate the room more often. The increased uranium content of some coals can lead to significant emissions of uranium and other radionuclides into the atmosphere as a result of fuel combustion at thermal power plants, in boiler houses, and during the operation of vehicles. Exists great amount commonly used items that are sources of radiation. This is, first of all, a watch with a luminous dial, which gives an annual expected effective equivalent dose 4 times higher than that caused by leaks at nuclear power plants, namely 2,000 man-Sv (“Radiation ...”, 55). Nuclear industry workers and airline crews receive an equivalent dose. Radium is used in the manufacture of such watches. In this case, the owner of the watch is exposed to the greatest risk. Radioactive isotopes are also used in other luminous devices: entry/exit signs, compasses, telephone dials, sights, fluorescent lamp chokes and other electrical appliances, etc. When producing smoke detectors, their operating principle is often based on the use of alpha radiation. Thorium is used to make especially thin optical lenses, and uranium is used to give artificial shine to teeth.

Radiation doses from color televisions and X-ray machines for checking passengers' luggage at airports are very small.

In the introduction, they pointed out the fact that one of the most serious omissions today is the lack of objective information. However, a huge amount of work has already been done to assess radiation pollution, and the results of research are published from time to time both in specialized literature and in the press. But to understand the problem, it is necessary to have not fragmentary data, but a clear picture of the whole picture. And she is like that. We do not have the right and opportunity to destroy the main source of radiation, namely nature, and we also cannot and should not give up the advantages that our knowledge of the laws of nature and the ability to use them gives us. But it is necessary

List of used literature

radiation human body radiation

1. Lisichkin V.A., Shelepin L.A., Boev B.V. Decline of civilization or movement towards the noosphere (ecology from different sides). M.; "ITs-Garant", 1997. 352 p.
2. Miller T. Life in environment/ Per. from English In 3 volumes. T.1. M., 1993; T.2. M., 1994.
3. Nebel B. Environmental Science: How the World Works. In 2 vols. / Transl. from English T. 2. M., 1993.
4. Pronin M. Be afraid! Chemistry and life. 1992. No. 4. P. 58.
5. Revelle P., Revelle Ch. Our habitat. In 4 books. Book 3.

Energy problems of humanity / Transl. from English M.; Science, 1995. 296 p.

6. Environmental problems: what is happening, who is to blame and what to do?: Textbook / Ed. prof. IN AND. Danilova-Danilyana. M.: Publishing house MNEPU, 1997. 332 p.