Ionizing contamination

The human being has always lived and evolved in the world filled with radio-activity and ionization. Biosphere of the Earth has more than 60 natural radionuclides - primary and cosmic. Primary radionuclides are isotopes of elements with long half-life and decay product of long living isotopes of uranium and thorium; cosmic – are some which appear after interaction of space radiation with substance of atmosphere or with solid substance of the earth. Every second human's body gets tiny particle through. Ground, walls of houses, air, food, person himself are radioactive. Therefore it is possible to assert that the natural background doze which influences the mankind for thousands of years is not dangerous because mankind got accustomed to such exposure during natural selection.

Researches done in the field of atomic nucleus and using nuclear energy create artificial sources of ionizing radiation. At the first stage of using nuclear energy the problem of radiation safety concerned only to staff that worked with nuclear arrangements and radioactive substances, in modern conditions when nuclear power's got fast development it is necessary to take into account global scattering of artificial radioactive substances and increasing rate of natural radionuclides circulation what predetermines an additional exposure on any living organism. The increasing of radiation factor in global scale has set a problem on development of principles for public health services with account of direct influence of ionizing radiation on objects of a natural medium.

Radioactive contamination of environment is caused by two types of radiation – corpuscular and electromagnetic. Corpuscular radiation includes flows of α – и β – particles and neutrons, electromagnetic one is χ-rays ( λ= 10 ⁹. 10 ^-12 m) and γ- radiation (λ<10 ^-12m). Corpuscular and electromagnetic radiation with indicated range of wavelength is able to split electrically neutral molecules forming charged ions during interaction with substance.

That's why the cumulative title of these types of radiation is ionizing.

Each of the mentioned above types of radiation has various properties and characteristics the most important of them are penetrating and ionizing abilities.

Source of ionizing radiation can be closed when radioactive substances can't penetrate into environment from installation, and opened, when such possibility exists.

The exposure of an organism can be external and internal. An external exposure is when the source of it can be outside of an organism, and internal - it's inside. The radioactive substances can get inside an organism with the air through respiration, as a radioactive dust, with water, food, smoke. The internal sources are more dangerous, because their influence on the organism is constant what results in accumulation of ionizing atoms and molecules.

The ionization of an organism is followed by complicated physical-chemical and biological processes, breaking of molecular bones, modification of molecules structure, killing cells, violation of normal physiological processes, exchange of substances are possible to refer to. Besides, the structure and functions of blood is infringed, the protective responses of an organism are reduced and the malignant swellings arise and develop. These and other symptoms characterize the so called radiation sickness which is fatal.

The special danger for biological world is in the fact that modifications occurring in an organism of people and animals under influence of radio-activity concerns only to them, but also the next generation which may nave inborn defects.

The radio-activity causes changes in all living things. Virus and bacterium being under exposure in future can form new mutations of morbific microbes and cause unknown epidemics.

In accordance to the standard «Нормы радиационной опасности» there are three categories of the people being under exposure set: A category is staff that constantly or temporarily works directly with sources of ionizing radiation; the category В – people who don't work directly with radiation sources, but in living conditions or working can get under the influences of radioactive substances, which are used at the appropriate technologies and expose into environment with waste; category С – rest of the country population.

Taking into account sensitivity of separate organs of the person to ionizing radiation they are divided into three groups (in order of decreasing of influence):

I - whole body, red marrow, genitals;

II - muscles, liver, kidneys, lungs, alimentary canal, eyeball;

III - skin, bones.

Using of atomic energy is not connected with the threat of an erasure of life on the Earth, but violation of norms and rules of radiation safety gets people under direct danger for health from radioactive substances. Therefore while projecting and constructing of power stations it is necessary to pay close attention to this problem. The main problem here is a problem of neutralization of nuclear industry waste.

Many countries practice radioactive waste burial at the bottom of the ocean. So into the Atlantic and Pacific oceans there were thrown hundreds of thousands of containers with high radio-active waste. The containers were rejected into deep-water areas with small circulation and low biological activity. However, as researches showed, in many areas intensity of circulation and biological activity had been increased.

The solid radioactive waste (polluted materials, workcloth etc.) are put into concrete trenches and filled up with concrete.