Laboratory and field studies of polonium and plutonium in marine plankton

The influence of particle concentration and composition on the fractionation of 210Po and 210Pb along the North Atlantic GEOTRACES transect GA03

“…These results support the well documented preference for 210 Po uptake over 210 Pb in marine 734 31 organisms and that 210 Po is both particle-reactive and bio-reactive, whereas 210 Pb is only 735 particle-reactive (Fisher et al, 1983;Heyraud et al, 1976;Heyraud and Cherry, 1979;Larock 736 et al, 1996;Stewart and Fisher, 2003;Wilson et al, 2009). The known bio-reactive behavior 737 of 210 Po and its association with sulfur (Balistrieri et al, 1995;Cherrier et al, 1995;Harada 738 et al, 1989), both suggest its cycling in particles is more complicated than 210 Pb cycling and 739 supports our hypothesis that important end-members were missing for the model of K d (Po).…”

210Po in the marine environment with emphasis on its behaviour within the biosphere

“…At the first trophic level Stewart and Fisher (2003a) have demonstrated that 210 Po is readily taken up by phytoplankton and, unlike certain other natural-series radionuclides, it can penetrate into the cytoplasm of cells making it potentially available for uptake by herbivores. In fact the uptake response is very rapid as is evident from a recent laboratory study in which the diatom Skeletonema costatum exposed to 210 Po-labelled sea water displayed an uptake half-time to equilibrium of only 0.6 days (Wilson and Watts, 2009). Two other experiments examining the food chain transfer of 210 Po bound to phytoplankton have shown that assimilation efficiencies of this radionuclide in herbivores are high, ranging from approximately 17% in mussels to 20e55% in copepod zooplankton (Table 6), and are dependent upon the algal species ingested (Stewart and Fisher, 2003b;Wildgust et al, 2000).…”

Kemampuan Kerang Hijau (Perna viridis) Mengakumulasi Plutonium Melalui Jalur Air Laut

“…Studi bioakumulasi plutonium kebanyakan dilakukan berdasar pemantauan lingkungan (Melinda et al, 2015). Wilson et al (2009) melakukan eksperimen bioakumulasi untuk mengetahui konsentrasi radionuklida plutonium pada sampel plankton yang dikumpulkan di Laut Irlandia Timur. Berbagai studi menggunakan pendekatan biokinetik telah dilakukan (Mrabet et al, 2013;Strumińska-Parulska et al, 2011), disisi lain studi terkait bioakumulasi oleh kerang hijau masih sangat terbatas.…”