Experimental study of the transfer of transuranium nuclides in marine decapod crustaceans

Abstract

A series of laboratory radiotracer experiments was carried out to examine the biolunetics of the transuranium nuclides plutonium, americium and neptunium in decapod crustaceans. Crabs Carcinus rnaenas exposed to 2 3 7~~ or 241Am in seawater reached whole body concentration factors (CF) of 75 and 145, respectively, after 8 d. Highest concentration factors for individual tissues were those for gills (CF = 960 for Am, 340 for Pu). For both radionuclides, about 7 0 % of total body burden was associated with the exoskeleton in which Am (CF = 240) was enriched relative to Pu (CF = 70). Elimination of each radionuclide was relatively rapid with biological half-times of 45 and 55 d for Am and Pu, respectively, for the slow release compartment. Because much of the accumulated body burden was associated with the exoskeleton, moulting strongly influenced elimination. 2 3 7~~, 2 4 1~m or 237Np ingested with labelled food by various decapod species were initially excreted with the feces, followed by loss from a soluble radionuclide pool within the animal. Absorption efficiencies for ingested transuranics ranged from 10 to 40 % with hlghest values in the largest decapods (C, lnaenas and Cancer pagurus) examined. Initially, absorbed radionuclides were mostly contained in the hepatopancreas; however, there is evidence for internal transfer of transuranics to other tissues, particularly those associated with the exoskeleton. Such high assimilation efficiencies differ markedly from the few tenths or hundredths of a percent typically found in vertebrate species and thus highlight the ability of decapods to assimilate and retain large fractions of transuranium nuclides incorporated in their prey.

Ferritin and hemocyanin: 210Po molecular traps in marine fish, oyster and lobster

“…This oligomeric copper-containing metalloprotein, synthesized in the hepatopancreas (Senkbeil & Wriston 1981), is able to bind different metal ions (Brouwer et al 1983), and the active site of metal fixation may be able to bind polonium. The binding of 210 Po on hemocyanin has not been previously demonstrated, but a role for this protein has been suggested in the internal transfer of some radionuclides (Guary & Fowler 1990). Although the HPLC ferritin fraction was not pure, it seems clear that the degree of 210 Po binding to lobster ferritin is probably similar to that of the other species of fish and molluscs, and in the case of lobster 210 Po appears predominantly associated with hemocyanin.…”

Transfer of radionuclides in aquatic ecosystems – Default concentration ratios for aquatic biota in the Erica Tool

“…Leaving the database void of entries in these cases is not Skwarzec and Falkowski (1988) and Guary and Fowler (1990). Sr Crustacean 1.5 NRPA (2000), Skwarzec and Falkowski (1988) and Guary and Fowler (1990). Tc Crustacean 2.5 Busby et al (1997), Kolstad and Rudjord (2005), Skwarzec and Falkowski (1988) and Guary and Fowler (1990).…”

“…Leaving the database void of entries in these cases is not Skwarzec and Falkowski (1988) and Guary and Fowler (1990). Sr Crustacean 1.5 NRPA (2000), Skwarzec and Falkowski (1988) and Guary and Fowler (1990).…”

“…Sr Crustacean 1.5 NRPA (2000), Skwarzec and Falkowski (1988) and Guary and Fowler (1990). Tc Crustacean 2.5 Busby et al (1997), Kolstad and Rudjord (2005), Skwarzec and Falkowski (1988) and Guary and Fowler (1990). Co Fish 6 a Ishii et al (1976), Ichikawa and Ohno (1974), Ancellin et al (1979), Van As et al (1975), Bourlat et al (1997), Jenkins (1969), Lanno and Dixon (1996), Chellappa et al (2003), Ben Ekanem et al (2004), Cameron (1985), and Nonnis-Marzano and Triulzi (1994).…”

AnaComp Program application to calculate137Cs transfer rates in marine organisms and dose on the man

“…The radionuclide uptake by marine organisms may be evaluated by the bioaccumulation factor which relates the ratio of the equilibrium activity in the organism and the sea-water. 1 The compartmental analysis is useful to define the quantitative distribution of the elements in different compartments, in function of time. 2,3 The AnaComp Program 4 employed here is a computational code to the analysis of kinetic data that allows the interpretation of the experimental results of a quantitative and kinetic way.…”