580 



Table 10. Average '"Sr Concentration in Sea Surface Waters, 1990-1991, pCi/1 (23] 



Calculations performed using models of radionuclide migrations in marine systems demon- 

 strate low levels of possible entry of radionuclides from LRW into the human body through food 

 chains. Even with a conservative approach, exposure doses for possible critical population groups 

 do not reach significant values and are not reliably different from doses caused by the natural and 

 technogenically altered radiation background. 



In the course of research on the subject. Summary Documents on the Disposal of Radioac- 

 tive Waste from Naval Facilities in Special Areas of the Sea between I960 and 1966, performed 

 in 1967, no increase in radionuclide activity in seawater, plankton, or commercial water life was 

 detected in areas of LRW discharges. Computational studies on the subject. Documents on the 

 Validation of the Draft "Sanitary Requirements for Disposal of Radioactive Waste at Sea" also 

 showed that discharges of regulated amounts of LRW would not lead to a hygienically significant 

 increase in the concentration of artificial radionuclides in seawater and commercial water life. 

 Actual values of LRW discharges were, as a rule, significantly lower than regulatory standards. 



Consequently, data from previous research permit us to draw the preliminary conclusion that 

 the LRW discharged from facilities of the Northern and Pacific Fleets and the Murmansk Mari- 

 time Shipping Line presents no significant radiation hygiene danger, either to the population as a 

 whole or to critical population groups (fishermen, residents of coastal areas). Further studies 

 could refine the above preliminary assessment of the effect of LRW, but are unlikely to substan- 

 tially alter it. 



It is more complicated to assess the effect of LRW disposal on the marine ecosystem and 

 marine biocenoses. Our knowledge of the circulations of substances in northern and polar ecosys- 

 tems is too fragmentary for final definite conclusions. For example, our knowledge is totally in- 

 adequate even in the area of hydrography. Recent discoveries of powerful bottom currents that 

 vary with the seasons and deep storms in which the rate of movement of water masses exceeds 

 several knots show the depth of our ignorance, even of apparently well-studied parameters of the 

 sea. 



A conclusion on the eflfect of LRW disposal on shaping radioecological conditions at sea re- 

 quires comprehensive comparative studies of marine water life over large areas [24-27]. A com- 

 parison of various local populations of vertebrates, invertebrates, microorganisms and algae is 

 needed. 



Such studies, even if they are energetically begun in the near future, will take several years. 



38 



