Risk: medical, radiation, ecological, social-hygienic monitoring. Radiation-Hazardous objects. Population. Personal. Shore technical bases. Methodology of medical risk assessment is an important tool of social-hygienic monitoring. Individual lifelong risk of occurrence of stochastic effects in population from all exposure sources for three regions of the North-West region of Russia in 2003 made from 2,3 10(-4) to 3,1(.)10(-4) cases, including cases due to the work of radiation-hazardous objects similar to 1,0(.)10(-6) cases (i.e. correlated with unconditionally accepted risk). Risk of the professionals changed from 1,6(.)10(-4) to 5(.)10(-5), i.e. it was ten times lower than acceptable level of personnel risks set at the level 1,0(.)10(-3). At transition to potential risks relative role of man-caused exposure increased, due to the high territorial concentration of radiation potential accumulated in the Northwest region. STB in Andreeva Bay and Gremikha village may serve as an example of such deviation. In this connection the nearest prospect of work in STB area is connected with system development of rules and limitations that will guarantee provision of: a) radiation safety of personnel and population, b) prevention of radioactive contamination of the environmental objects and c) necessary level of radiation control at rehabilitation and management of radioactive wastes. Russian Federal Law "About Technical Regulation" defines risk as "probability of dandification to life and health of citizens, property of natural and juridical persons, state and municipal property, the environment, life and health of animals and vegetation with taking into account weight of this". This definition corresponds to total risk, as it integrates several diverse components - not only medical risk but ecological and property risk. It is obvious that total risk can be assessed only on the basis of preliminary profound separate assessment of each of the components, after which a possibility arises of comparatives characteristic of different by its nature risks on the basis of unified ratio of measurement of social-economical and material consequences of their realization (e.g. estimation appraisal). In the field of environmental hygiene in USSR due to the ideological strategy of absolute safety the term "risk" was substituted by the notion "danger" and only since the mid of 90-s an understanding of risk in the environmental hygiene as probability appeared in Russia [1]. However in respect to radiation hygiene no similar ideology was observed and all radiation regulation of radiation factor was based and is based at present on the concept of acceptable (admissible) risk [2]. However it should be stressed that due to different reasons at present there no unified approach and basic philosophy of ecological (radiation)l risk assessment in international experience. Let's look into medical component of possible risk of the discussed nuclear projects implementation because, as it follows from existing conceptions, provision of radiation safety to people in certain territories automatically prevent development of radio ecological consequences for them. In the scientific or close to the scientific lexicon such definitions as "ecological rehabilitation", "green and brown lanes" are often used. However unfortunately there are no acceptable scientifically grounded "visual" criteria of such kind. Apparently that's why in the frame of ICRP at the last session in China a special (fifth) ecological commission was organized with the purpose to formulate principals of ecological-radiation protection taking into account available scientific knowledge. During last years in the works [37] assessments of ecological dose limits are given, which for dominants of different ecosystems make from 20 to 500 Gy, and basic dose limit for animate nature 4-10 Gy/year is proposed. If we correlate it with 1 mSv (in accordance with the Russian norms of radiation safety - NRB -99 [8] the basic dose limit for population makes I mSv), ratio of difference will make 10(3)-10(4). At levels of radioactive contamination of the environment regulated by NRB-99 applicable to human maximum doses of biota exposure make 0,5 Gy/year, i.e. they are 20 times lower than basic dose limit for animate nature (10 Gy). Stated above stressed one more time that backbone unit of general radioecological safety is a human. At that in accordance with ICRP postulate if man is adequately protected by radiological standards then biota are also adequately protected. During many years in Russia and foreign countries methodology of medical radiation (non-chemical) risk assessment is used at control of radiation safety and assessment of consequences of ionizing exposure impact on human health. Scientific precondition of assessment of medical radiation risk are levels of carcinogenic risks of low-intensity radiation impact. At applying epidemiological approach, e.g. at studying the Japanese -A-bombs survivors, an opportunity appears to assess possible risk level. Ten years ago there were works that showed possibility of exceeding risks at exposure doses with low LPE of 50-100 mGy [9, 10]. In a number of other works analyzing data for A-bomb survivors are quite opposite, it stated that at doses lower that 300 mGy additional risk is absent and in some other cohorts risk is traced only at doses that exceed ratios traced in A-bomb survivors. Recently published works [11, 12] prove this, in which on the basis of careful epidemiological analyses of effects in the doses range of 100-3000 mGy, considerably lower (almost 5 times less) coefficients of risks of leucosis outputs and twice times -output of solid tumors are presented. "Chernobyl" epidemiology among all carcinogenic effects traced only significant acceleration of thyroid cancer [13]. At that in accordance with ICRP problems connected with risk assessment at exposure levels characteristic for professional conditions and the environment [14]. Since there is no reason to suggest zero risk, certain limited risk value is accepted in the system of radiation protection. Thus for annual doses of professional exposure level of lethal risk can make 10(-3), i.e. I case for 1000 persons. ICRP defined 0,3 mSv per year as acceptable maximum dose from single source for persons from population [15]. At this level of risk of lethal cancer makes about 10(-5) per year. Level of death risk, equal to 10(-6) per year is usually considered as insignificant and corresponding to it annual dose - about 10-20 mkSv - is accepted as criteria at which there is no necessity to consider measures of individual protection. Identified levels of medical radiation risk underlie native regulation of radiation factor. Radiation risk accordingly to NRB99 is a probability of appearance of some harmful effect in human and his descendants in result of exposure(2). Since uncertainty in risk assessment conditioned by biology and by epidemiology still exist, it should be remembered that man-caused radiation effects are always an addition to existent natural background radiation by several mSv/year. Because of the uncertainty of precise scientific data, at present ICRP consider new approach to protection [16], which will be presented in ICRP recommendations - 2005. Scientific studies of radiation risks for health in Russia since the foundation of nuclear industry and up to the present are based on monitoring data of the big radiation-hygienic "tree" (Fig. 1), on the branches of which there is monitoring: around radiation-hazard objects, since 1946 fallout products of nuclear exposures, since 1962 after Chernobyl accident, since 1986 radiation-hygienic certification(3), since 1999 and, finally, appearance of collective branch - social hygienic monitoring (SHM), since 2000. Radiation hygienic monitoring (RHM), on which native system of medical risks assessments is based, is an important component of SHM. Today methodology of medical risk assessment has become one of the most important SHM tools(4). Social hygienic monitoring (SHM) is the system of state surveillance, analysis, assessment, and prognosis of the population health and habituated environment as well as the correlation of the population health versus the habituated environment factor exposure. By definition SHM is based on "three whales" (Fig.2). At solution of the problem of health conditionality (first "whale") it is not enough to define and enumerate diverse effects on it (third "whale"), it is necessary to find key conditions and factors of risk (second "whale"). We use this scheme in order to conduct study on medical risk assessment in an adequate way, as well as to illustrate principal construction of work which stipulates for scientific assessment of health condition. "Three whales" is a general scheme of vision of health study from medical risk aspect. Purpose of the present report is to give an account of state of affairs of results of medical risk assessment for one of SHM sections (third "whale" with its subsection radiation), i.e. for provision of radiation safety on the basis of medical risk assessment in respect to functioning of nuclear objects. By this presentation we do not solve final problems of methodology of medical risk assessment but come near to theirs.
