Detection and temporal variation of (60)Co in the digestive glands of the common octopus, Octopus vulgaris, in the East China Sea.
(60)Co were detected in common octopus specimens collected in the East China Sea in 1996-2005. The source of (60)Co has remained unclear yet. Stable isotope analyses showed that there was no difference in stable Co concentrations between octopus samples with (60)Co and without (60)Co. This result showed that the stable Co in the digestive gland of octopus potentially did not include a trace amount of (60)Co and the source of (60)Co existed independently. Furthermore, investigations of octopus in other area and other species indicated that the origin of the source of (60)Co occurred locally in the restricted area in the East China Sea and not in the coastal area of Japan. Concentrations of (60)Co have annually decreased with shorter half-life than the physical half-life. This decrease tendency suggests that the sources of (60)Co were identical and were temporary dumped into the East China Sea as a solid waste.
Morita
Takami
T
Marine Productivity Division, National Research Institute of Fisheries Science, Fisheries Research Agency, Japan. takam@affrc.go.jp
Otosaka
Shigeyoshi
S
Fujimoto
Ken
K
Nishiuchi
Kou
K
Kimoto
Katsunori
K
Yamada
Haruya
H
Kasai
Hiromi
H
Minakawa
Masayuki
M
Yoshida
Katsuhiko
K
D000818:Animals; D002588:Cesium Radioisotopes / Q000378:metabolism; D003036:Cobalt Isotopes / Q000378:metabolism; D003037:Cobalt Radioisotopes / Q000378:metabolism*; D004064:Digestive System / Q000378:metabolism; D009132:Muscles / Q000378:metabolism; D009792:Oceans and Seas; D049831:Octopodiformes / Q000378:metabolism*; D011834:Radiation Monitoring; D011868:Radioisotopes / Q000378:metabolism; D012834:Silver / Q000378:metabolism; D014875:Water Pollutants, Radioactive / Q000378:metabolism*
D002588:Cesium Radioisotopes; D003036:Cobalt Isotopes; D003037:Cobalt Radioisotopes; D011868:Radioisotopes; D014875:Water Pollutants, Radioactive; D012834:Silver