137Cs in waters and bottom sediments of the Sea of Japan in 2002 and 1994

During an expedition aboard R/V Pavel Gordienko (September, 2002) investigations in the Sea of Japan areas, where radioactive wastes were disposed by the former Soviet Union, were carried out in order to assess present level of radioactive contamination of marine environment. Concentration of I37Cs, radioecologically one of the most important radionuclides, in near-bottom sea water and bottom sediments were measured to be low, 2.8-17.2 Bq/m**3 and 3.2-27.2 Bq/kg dry weight, respectively, that did not differ significantly from levels elsewhere in the northwest Pacific Ocean arising from global fallout. Results of measurements were compared with results of the Joint Japanese- Korean -Russian expedition to the Sea of Japan in 1994

(Table 6a) 137Cs concentrations in waters of the Sea of Japan in 1994 and in 2002

Sulfide, S°, and thiosulfate were determined in waters of the Baltic Sea. Microquantities of these compounds were observed in oxic waters. Concentration levels of reduced sulfur compounds in Baltic oxic waters were very close to levels of the Black Sea oxic zone. Thiosulfate and S° were predominate compounds in oxic water whereas sulfide was a predominant compound Baltic waters high in hydrogen sulfide. Conclusion was made that during sedimentation in oxic waters anaerobic microorganisms along with aerobic bacteria take part in mineralization of organic matter. They exist on surfaces and in microniches of particles of organic detritus

(Table 6b) 137Cs concentrations in surface layer bottom sediments of the Sea of Japan in 1994 and in 2002

Sulfide, S°, and thiosulfate were determined in waters of the Baltic Sea. Microquantities of these compounds were observed in oxic waters. Concentration levels of reduced sulfur compounds in Baltic oxic waters were very close to levels of the Black Sea oxic zone. Thiosulfate and S° were predominate compounds in oxic water whereas sulfide was a predominant compound Baltic waters high in hydrogen sulfide. Conclusion was made that during sedimentation in oxic waters anaerobic microorganisms along with aerobic bacteria take part in mineralization of organic matter. They exist on surfaces and in microniches of particles of organic detritus