Concentrations of 137Cs, 90Sr, 108m Ag, 239+240 Pu and atom ratio of 240Pu/239Pu in tanner crabs, Chionoecetes japonicus and Chionoecetes opilio collected around Japan.
The anthropogenic radionuclides, (137)Cs, (90)Sr, (108m)Ag, (239+240)Pu, were measured in two Chionoecetes species, red queen crab (Chionoecetes japonicus) and snow crab (Chionoecetes opilio) collected around Japan during 1996-2007. There was no increase in the concentrations of these radionuclides and no large variation of the atom ratio of (240)Pu/(239)Pu during this research period. These results indicated that the source of the radionuclides was not the radioactive wastes dumped by the former USSR and Russia and originated from past nuclear weapon tests. The higher atom ratio in the crab species than that from global fallout would be contributed by the Pacific Proving Grounds close-in fallout. The variability of the concentration of radionuclides in the crab species would result from the variability of the composition and quantity in the diet. However, the decrease in the concentration of radionuclides with sampling depth would depend on the concentration in the seawater and diet.
Morita
Takami
T
Marine Productivity Division, National Research Institute of Fisheries Science, Fisheries, Research Agency, Japan. takam@affrc.go.jp
Ohtsuka
Yoshihito
Y
Fujimoto
Ken
K
Minamisako
Yoko
Y
Iida
Rika
R
Nakamura
Masae
M
Kayama
Toshiharu
T
D000818:Animals; D003386:Brachyura / Q000378:metabolism*; D002588:Cesium Radioisotopes / Q000378:metabolism*; D007564:Japan; D011005:Plutonium / Q000378:metabolism*; D011834:Radiation Monitoring; D012834:Silver / Q000378:metabolism*; D013326:Strontium Radioisotopes / Q000378:metabolism*; D014875:Water Pollutants, Radioactive / Q000378:metabolism*; D014878:Water Pollution, Radioactive / Q000706:statistics & numerical data
D002588:Cesium Radioisotopes; D013326:Strontium Radioisotopes; D014875:Water Pollutants, Radioactive; D012834:Silver; D011005:Plutonium