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An extensive programme of experiments on transfer of radionuclides to aquatic species was conducted in the former USSR starting from the early 1950s. Only a few of these studies were made available in the English language literature or taken into account in international reviews of radionuclide behaviour in marine ecosystems. Therefore, an overview of original information on radionuclide transfer to marine biota species available from Russian language literature sources is presented here. The concentration ratio (CR) values for many radionuclides and for marine species such as: 239Pu ²³⁹Pu, 106Ru ¹⁰⁶Ru and 95Zr ⁹⁵Zr (crustacean), 54Mn ⁵⁴Mn, 90Sr ⁹⁰Sr, 95Nb ⁹⁵Nb, 106Ru, 137Cs 239Pu, 241Am ¹⁰⁶Ru, ¹³⁷Cs ²³⁹Pu, ²⁴¹Am and natural U (molluscs), and 54Mn, 90Sr, 137Cs and 144Ce (fish) are in good agreement with those previously published, whilst for some of them, in particular, for 32P and 110Ag (crustaceans), 35S (molluscs), 32P ³²P, 35S ³⁵S, 95Nb ⁹⁵Nb, and 106Ru ¹⁰⁶Ru (macroalgae) and 60Co ⁶⁰Co and ^239,240Pu ²⁴⁰Pu (fish) the data presented here suggest that changes in the default CR reference values presented in recent marine reviews may be required. The data presented here are intended to supplement substantially the CR values being collated within the handbook on Wildlife Transfer Coefficients, coordinated under the IAEA EMRAS II programme.

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For the estimation of radiation doses to organisms, concentration ratios (C R sCRs) of radionuclides are required. In the present study, C R s CRs of various elements were obtained as analogues of radionuclides for algae, molluscs, and crustaceans, in eight estuarine areas around Japan. The elements measured were Na, Mg, K, Ca, V, Mn, Fe, Co, Ni, Cu, Rb, Sr, Y, Mo, Cd, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Pb, and U. The geometric mean (GM) values of C R s CRs (GM-C R sCRs) for alkali and alkaline earth elements, Mo, and U for all biota, as well as V for crustaceans, were less than 100 L/kg, while GM-C R s CRs for the other elements were higher. When the obtained GM-C R s CRs were compared with the C R s CRs recommended in IAEA Technical Report Series 422 for marine organisms, no big differences between them were found; however, several elements (i.e. Cd and U for algae, Mn for molluscs, and Pb for crustaceans) were lower than the recommended C R sCRs. In the present study, conversion factors (the ratio of C R CR for the whole body to that for muscle) for molluscs and crustaceans were also calculated, since data on edible parts of these organisms are generally available in the literature. For crustaceans, GM conversion factors of all the elements were more than one. For molluscs, GM conversion factors of rare earth elements and U were slightly higher than those for crustaceans, while GM conversion factors of the other elements were almost the same and less than 10. These results indicate that some elements tend to be concentrated in the internal organs of biota collected in the estuarine areas. For environmental radiological assessment, conversion factors from tissue to whole-body C R CR values are useful parameters.

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Radionuclide concentrations in Australian terrestrial fauna, including indigenous kangaroos and lizards, as well as introduced sheep and water buffalo, are of interest when considering doses to human receptors and doses to the biota itself. Here, concentration ratio (CR) values for a variety of endemic and introduced Australian animals with a focus on wildlife and livestock inhabiting open rangeland are derived and reported. The CR values are based on U- and Th-series concentration data obtained from previous studies at mining sites and 241Am ²⁴¹Am and ^239/240Pu ²⁴⁰Pu data from a former weapons testing site. Soil-to-muscle CR values of key natural-series radionuclides for grazing Australian kangaroo and sheep are one to two orders of magnitude higher than those of grazing cattle in North and South America, and for 210Po ²¹⁰Po, 230Th ²³⁰Th, and 238U ²³⁸U are one to two orders of magnitude higher than the ERICA tool reference values. When comparing paired kangaroo and sheep CR values, results are linearly correlated (r = 0.81) for all tissue types. However, kidney and liver CR values for kangaroo are typically higher than those of sheep, particularly for 210Pb ²¹⁰Pb, and 210Po ²¹⁰Po, with values in kangaroo liver more than an order of magnitude higher than those in sheep liver. Concentration ratios for organs are typically higher than those for muscle including those for 241Am ²⁴¹Am and 2392^39/240Pu ²⁴⁰Pu in cooked kangaroo and rabbit samples. This study provides CR values for Australian terrestrial wildlife and livestock and suggests higher accumulation rates for select radionuclides in semi-arid Australian conditions compared with those associated with temperate conditions.

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There is a scarcity of data on transfer of both natural and anthropogenic radionuclides to detritivorous invertebrates for use in the assessment of radiation exposure. Although mosses and lichens have been extensively used in biomonitoring programs, the data on transfer of radionuclides to these species are limited, particularly for natural radionuclides. To enhance the available data, activity concentrations of 137Cs ¹³⁷Cs, 226Ra ²²⁶Ra and 228Ra ²²⁸Ra were measured in ants, mosses and lichens and corresponding undisturbed soil collected from semi-natural ecosystems in Serbia and Montenegro and biota/soil concentration ratios (CR) calculated. Since the majority of internal dose to biota is expected to come from 40K ⁴⁰K, the activity concentrations of this radionuclide were also determined. The mean CR values for 137Cs ¹³⁷Cs, 226Ra ²²⁶Ra and 228Ra ²²⁸Ra in ants analyzed in this study were found to be 0.02, 0.06 and 0.02, respectively. The mean CR values of radionuclides in mosses were found to be 2.84 for 137Cs ¹³⁷Cs, 0.19 for 226Ra ²²⁶Ra and 0.16 for 228Ra ²²⁸Ra, while those in lichens were found to be 1.08 for 137Cs ¹³⁷Cs, 0.15 for 226Ra ²²⁶Ra and 0.13 for 228Ra ²²⁸Ra. The CR values obtained in this study were compared with default CR values used in the ERICA Tool database and also with those reported in other studies.

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