Ž . The Science of the Total Environment 237238 1999 203212 Anthropogenic radionuclides in seawater of the Far Eastern Seas Y. Ikeuchi a,  , H. Amano b , M. Aoyama c , V.I. Berezhnov d , E. Chaykovskaya e , V.B. Chumichev d , C.S. Chung f , J. Gastaud g , K. Hirose c , G.H. Hong f , C.K. Kim h , S.H. Kim f , T. Miyao c , T. Morimoto a , A. Nikitin d , K. Oda i , H.B.L. Pettersson j , P.P. Povinec g , A. Tkalin e , O. Togawa g , N.K. Veletova d a Japan Chemical Analysis Center, 295-3, San-no-cho, Inage, Chiba 263-0002, Japan b Department of En ironmental Safety Research, Japan Atomic Energy Research Institute, Tokai, Ibaraki 319-1106, Japan c Geochemical Research Department, Meteorological Research Institute, Nagamine 1-1, Tsukuba, Ibaraki 305-0052, Japan d Laboratory for Monitoring of Water Bodies Radioacti  e Contamination, ‘Typhoon’, Obninsk 249020, Russia e Regional Radiochemical Laboratory, Far Eastern Regional Hydrometeorological Research Institute, 24. Fontannaya Str., Vladi  ostok 6090660, Russia f Isotope Oceanography Laboratory, Korea Ocean Research and De  elopment Institute, Ansan, Seoul 425-600, South Korea g Marine En ironment Laboratory, International Atomic Energy Agency, Monaco h Department of Radiochemical Analysis, Korea Institute of Nuclear Safety, Daeduk-Danji, Daejon 305-606, South Korea i Marine Pollution Laboratory, Hydrographic Department, Maritime Safety Agency, Tsukiji 5-3-1, Chuuo, Tokyo 104-0045, Japan j Department of Radiation Physics, Uni  ersity of Linkoping, S-581 85, Linkoping, Sweden ¨ ¨ Abstract Large quantities of radioactive wastes have been dumped in the Far Eastern Seas by the former Soviet Union and the Russian Federation, and small amounts of radioactive wastes have been dumped by Japan and the Republic of Korea. In order to investigate the concentrations of anthropogenic radionuclides in the nine dumping areas, a second expedition was conducted in 1995 by Japan, the Republic of Korea, the Russian Federation and IAEA, following the first expedition in 1994. The results show that 137 Cs, 90 Sr and 239240 Pu concentrations in surface and bottom waters at dumping areas do not significantly differ from the values observed in background areas, and from historical values. There is no clear effect of possible contamination due to radioactive waste dumping. The concentrations and water  Corresponding author. Tel.: 81-43-423-5325; fax: 81-43-423-8660. Ž . E-mail address: y-ikeuchi@jcac.or.jp Y. Ikeuchi 0048-969799$ - see front matter  1999 Elsevier Science B.V. All rights reserved. Ž . PII: S 0 0 4 8 - 9 6 9 7 99 00136-9