The unceasing interest of Tajikistan press towards radiation and unstopping dig of radiationally dangerous objects by “prospectors” searching for non - ferrous and other sorts of metals make us invoke this theme the recurrent time. It’s not occasional that at the meeting of regional activists viloyat governor Qosim Qosimov reminded about last publications in different newspapers pointing to perfunctory approach of journalists, and sometimes experts towards a preparation of the material dwelling on tail repositories, radiation atmosphere in Northern Tajikistan. All specialists and leaders being interested in ecology questions evoked by press perceived his emotional utterance dealing with the uranium problem inherited by us from the Soviet period and caused by our predecessors. “And we have to appoint ourselves in charge of this heritage which in due time was necessary for the reinforcement of the defense capacity of the vast country - that of the USSR, - told Q. Qosimov, - we ought to bear the brunt of it, solving complicated problems, relieving its aftermath for our descendants”.
The last publications dwelling on this issue really resemble the stir produced by the republican newspapers in early 90-ies speckling with disturbing titles: “Holes in the Fortress of Death”, “Local Chernobyl”… The experts of Leninabad mining combine (now “Vostokredmet” SOE (state-owned enterprise)) spent a lot of time answering endless requests of ecology enthusiasts and prosecutor’s offices of diverse ranges. Most of all they wanted the indignant citizens to take part in cotrolling measurements of the locality together with them. Among the experts there was always the chief of the environmental protection section under the enterprise Leonid Pavlyuk who agreed gallantly to comment upon the theme in question.
- Leonid Mikhailovich, doesn’t it seem to You that the troubles of population in regard to the allegedly rising radiation background in the viloyat are caused rather by the non-availabilyt of elementary knowledge in this direction? Even from school manuals we do know that each one of us “catches” radiation from a domestic television-set.
- I would like such conversations to be conducted at schools and villages, in higher educational establishments and in the organizations people are socially engaged. The absence of ecology literacy not only makes people spread rumors but commit actions which may entail tragic consequences for them themselves either. And really, we collide with radiation every now and then. But philistines gathered the impression that it affects mostly dangerously only in Chkalovsk, Taboshar, Adrasman and on the Mogol-Tay slopes - near the northern-eastern micro districts of Khujand where the extraction of uranium-containing ore was carried out. Uranium is present on the Earth ubiquitously. Average concentration of uranium in the earth-crust is 4 grams per a ton of mountainous mass. In the coursee of the entire history man lives being affected by natural sources of radiation (cosmis rays, mountainous rock, soil and etc.). Natural sources of radiation constitute natural background.
Man’s activity eventuated into artificial sources of radiation as well. For example, a colored TV-set near which our citizens got used to have meals, to play with children. Daily 3-hours watching throughout a year gives a radiation dose of 0.5 mbers (0.5 mr, 500 mcr). Many organizations of geology, construction, medicine in our viloyat are connected with radiation. For example, people are hardly imagined to pay attention to the appliances of antifire signalization installed in the rooms of an organization or an enterprise. Meanwhile, all of them are artificial sources of ionizing radiation (IRASs). IRASs are capsules out of brasss or stainless steel of about 1 cm in diameter and 6-7 cm in length. I talked with children from Chkalovsk, Khujand, Ghoziyon, Taboshar in this topic: for them it is a curious toy! Even senior pupils are convinced of it. Nobody of those questioned knew that if such a thing gets in your hands one mustn’t touch it and, moreover, you ought not to dismantle it! It is necessary to notify militia and authoritie, as these capsules contain highly active isotopes and if you touch them you may suffer radiation burns with heavy aftermath for your health.
The wastes of the uranium-processing industry also pertain to artificial sources of radiation. And since the first days of such outfits being launched the primary goal was a non-admission of processed products leakage beyond the boundaries of the enterprise neither in solid nor in liquid state; that being identical to environmental protection from pollution. But any processing outfit, be in agriculture, light or food industry, can’t work without wastes. Thereof there appeared 50 years ago a repository of solid low radioactive wastes in the town of Ghafurov interred according to a special project. As for the theme of radioation, it caused the keen and broad interest of people after the wreckage of Chernobyl AES. The explosion showed that both in peaceful time imcompetent usage of atomic energy may result into a great tragedy for population and nature.
There are three uranium provinces on the territory of our viloyat - that what is createdd by nature. Radiation here is associated with artificial disposal of radiation sources. Natural sources being scattered widely in mountainous mass with their radioactive elements included into ore compositions are practically non-dangerous. But in the boundaries of provinces they tapped deposits, uranium ore was processed with uranium extraction and the residues of ore (wastes) were dispatched to certain spots - repositories where the wastes being of certain radiation danger were concentrated in one place. Repositories of wastes are overlapped with radiotionally neutral soil of no less than 50 cm thick that permits to ensure their safety for people and nature. But construction, vegetable-gardens, pipelines, and of course, excavations are forbidden on the places of repositories. Why? When radioactive wastes are opened man will be in touch with them whether he wants it or not.
- And to what extent is it dangerous? And why?
- The wastes of uranium ores processing contain radioactive stuffs - radionuclides of natural origin which possess the properties of spontaneous distintegration, hereby they emanate Alpha-, Beta and Gamma-particles.
Alpha-particles have low speed of streaming, about 10 cm of running and minor penetrating capacity (they are barred with a paper screen). They are dangerous as they may get into a human body (with air into lungs or to digention organs from dirty hands).
Betta-particles have sublight speed, great streaming speed and big penetrating capacity.
Gamma-particles are a tough emanation of great energy and streaming speed, they possess a big penetrating capacity. Alpha and Beta-particles under inward or outward affection upon man’s body in cellular level split molecules of water (radiolits), and insomuch as a human organism consists of water making up 75%, there are forms a big quantum of OH and H radicals which oxidize the molecules of protein; in the outcome the functions of body’s activity disappear.
Tough Gamma-rays under direct affection split protein molecules, tear apart intercellular ties and create irrevertible changes in an organism.
Radioactivity (Gamma-radiation dose power) is measured in Roentgens (R); biological equivalent of Roentgen is ber (degree of radiation affection upon man). Roughly 1R=1 ber. Roentgen derivatives are milli-Roentgen, mR (one thousandth of Roentgen) and microRoentgen mcR (millionth of Roentgen). Why do we operate with Gamma-radiation? Because the latter is mostly dangerous for man, the degree of radioactive source danger is characterized by it. For simplicity we shan’t speak about other magnitudes qualifying a source of radiation.
An average yearly radiation dose caused upon man by nature radiation background makes up approximately 0.001 ber (1 mber, 1000 mcber) and depends on the locality man lives in. in the left-bank part of Khujand natural background is measured in the limits of 15-20 mec/hour, on the right bank being closer to mountains - up to 4050 mcr/hour. I stress - micro Roentgens an hour! It is what is allowed to us by nature.
- Not very long ago there was a tradition in Chkalovsk to hang bulletins on ecology atmosphere in the town with indication of radiation safety norms in animated places. It was quite natural for citizens. But today when only any newspaper publishes indicators of the background people are panic-stricken. Do you remember how Your production was accused of intensified ailments, premature child deliveries, birth of children-invalids in the vicinities?
- Yes, I do, there were such things. Today we also hear rebukes to our address. We’ve got tired of our Chkalovsk being exemplified. At the time when uranium processing production worked still, a rigid approach of Chkalovsk medical-sanitary unit under our combine was rather akin to the Center of cosmonauts training. Annual medical examination of our professionals didn’t register any professional disease even at the mining-metallurgic plant (MMP) where dose limits of radioactivity for the personell are 2900 mcR/hour. We consider the statements of high rank officials of our objects affecting a formation of malignant tumors as indelicate. It should be put down rather to bad drinking water, poisonous chemicals, poor nourishment. As for the higher oncology indicator in Chkalovsk in comparison with the viloyat, it testifies to more authentic diagnostics and registration of our patients by our onlocogy service being unrelated to radiation factors. One must take into consideration the fact that the major part of our staff connected with the production for a long time left Tajikistan and the same quantity of people from other areas of the country arrived for the latest 10 years to occupy job vacancies. In addition, as the oncology service reports, the number of registered patients over the town multiplies in the distance between the industrial site and the airport. And one thing more: in 1996 there were registered 280 oncology patients, in 2001-121; the quantum is diminishing.
It is worth mentioning that the absolutely lethal dose for man under one-time-radiation is 700 R. Breaches in the body (skin peeling, nausea, vomit, obfuscation of crystalline lens, affection of blood system) appear under 50 R dose.
- And how can we ourselves reduce radiation influence upon our body?
- First of all, to reduce the time, i.e. under an equal power of a radiation source the shorter the time you contact with it is the less dose you will get. In the second, by distance.for example, if you stand or sit at the distance of 2 meters from a TV-set for two hours you will get a dose in 1 mcR, but at the distance of 5 cm - 10000 mcR. And in the third, this dose diminishes depending on the density of barring material between source and man. When radionuclides get inside the body (through the organs of respiration and igestion, through skin) there appears inward radiation of man being much more dangerous than outward one. Inward radiation is reduced by partial withdrawal of nuclides out of the body and their natural disintegration. The most dangerous thins is when radionuclides get into the body through organs of respiration. And if man in his professional activity has nothing to do with uranium ore then inhaling radon when often indoors is mostly dangerous. Scientists understood it only quite recently. Radon and the products of its disintegration are invisible, they have neither taste nor smell. A minor part of radon is exuded indoors, in residential houses and produciton buildings from building materials, a major part - from soil. Radon possesses the properties of accumulating in the body, thus it enhances concentration and affecting factors. Thereof, the main things under the combat with radon indoors are:
- Not to take building materials for construction in precarious places, for example, from factory repositories, mine slag-heaps;
- Not to use granite for inward decoration of buildings;
- Permanently to air rooms, especially bath-rooms where radon may reach with water, kitchens where it comes with natural gas.
Thus, only literate handling with artificial and natural sources of ionizing emanation; exclusion of direct contacts with them, observance of sanitary-hygienic rules will remove a menace for life and health of our population. All of us should bring to the notice of mardikors (unskilled laborers) who are sent to by rich clients to tail repositories and conserved pits for metallic constructions and paid meagre pennies for their job that their digs and attendance of mining gallereys may cause a lot of harm to their and our health, to reflect on that one of progeny.