Distribution of global fallout237Np, Pu isotopes, and241Am in lake and sea sediments

Vertical distributions of Pu and radiocesium isotopes in sediments from Lake Inba after the Fukushima Daiichi Nuclear Power Plant accident: Source identification and accumulation

“…4. These Pu inventories, like the 239+240 Pu activities, were significantly lower than those of Lake Tamogi, Takahoko, Ichiyanagi, Kugushi,Mikata, Bq/m 2 ) (Yamamoto et al, 1991;Ueda et al, 2004;Ueda et al, 2009). A possible explanation for this difference was that the previously investigated lakes mentioned above were located at 40-50 ºN and they received greater amount of Pu isotopes from global fallout (ca.…”

“…The activities of 239+240 Pu in Japanese lakes (Lake Obuchi, Kizaki, Kugushi, Ichiyanagi, Towada, Tamogi, and Takahoko) have been investigated and overall ranged from 0.02 to 7.00 Bq/kg before the FDNPP accident (Yamamoto et al, 1991;Nagao et al, 1999;Ueda et al, 2004Ueda et al, , 2009Zheng and Yamada, 2005). Clearly, the analytical results for 239+240 Pu activities (0.001-0.307 Bq/kg) in Lake Inba were within the range of the expected preexisting level.…”

“…Clearly, the analytical results for 239+240 Pu activities (0.001-0.307 Bq/kg) in Lake Inba were within the range of the expected preexisting level. Among the lakes mentioned above, the highest 239+240 Pu activity around 7.00 Bq/kg was observed in Lake Kugushi; this lake was influenced by a large inflow from a river into the lake of fine particulate materials that had adsorbed high amount of radionuclides (Yamamoto et al, 1991).…”

Distribution and source of 129 I, 239 ,240 Pu, 137 Cs in the environment of Lithuania

“…The 239,240 Pu/ 137 Cs activity ratio of 0.018 and 238 Pu/ 137 Cs activity ratio of 0.00068 the representative value of global fallout in soil were determined by Bunzl and Kracke in 1988 [21]. The 239,240 Pu/ 137 Cs activity ratio of 0.12 to 0.28 was found in the marine and lake sediments as the source of global fallout [17]. The 239,240 Pu/ 137 Cs activity ratio for the Chernobyl accident releases was observed to be 6.8 in the mushroom sampled in the 30km zone of the Chernobyl NPP [18].…”

“…The half-life of cesium-137 is relatively short (30.1y), nevertheless it is still possible to use this radionuclide for identification of source of the contamination. The main source of this isotope in the environment were the Chernobyl accident and nuclear weapon testing [17]- [20]. The 239,240 Pu/ 137 Cs activity ratio of 0.018 and 238 Pu/ 137 Cs activity ratio of 0.00068 the representative value of global fallout in soil were determined by Bunzl and Kracke in 1988 [21].…”