Novel DGT Configurations for the Assessment of Bioavailable Plutonium, Americium, and Uranium in Marine and Freshwater Environments

This article references 53 other publications.

1. 1

   Aldridge, J. N.; Kershaw, P.; Brown, J.; McCubbin, D.; Leonard, K. S.; Young, E. F. Transport of Plutonium (239/240Pu) and Caesium (137Cs) in the Irish Sea: Comparison between Observations and Results from Sediment and Contaminant Transport Modelling. Cont. Shelf Res. 2003, 23, 869– 899,  DOI: 10.1016/S0278-4343(03)00047-5

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2. 2

   Ryan, T. P.; Dowdall, A. M.; Long, S.; Smith, V.; Pollard, D.; Cunningham, J. D. Plutonium and Americium in Fish, Shellfish and Seaweed in the Irish Environment and Their Contribution to Dose. J. Environ. Radioact. 1999, 44, 349– 369,  DOI: 10.1016/S0265-931X(98)00140-4

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   Plutonium and americium in fish, shellfish and seaweed in the Irish environment and their contribution to dose

   Ryan, T. P.; Dowdall, A. M.; Long, S.; Smith, V.; Pollard, D.; Cunningham, J. D.

   Journal of Environmental Radioactivity (1999), 44 (2-3), 349-369CODEN: JERAEE; ISSN:0265-931X. (Elsevier Science Ltd.)

   Plutonium and americium activity concns. in fish and shellfish landed in Ireland in the period 1988 to 1997 are presented. Activity concns. in fish are low and often below detection limits, while those in mussels and oysters sampled on the northeast coast show no significant signs of decline. The estd. doses to hypothetical typical and heavy seafood consumers remain below 1 μSv yr-1 (committed ED). Plutonium activity concns. measured in Fucus vesiculosus around the Irish coastline have not fallen appreciably in the ten-year period between 1986 and 1996. Furthermore, the mean 238Pu/239,240Pu ratio of 0.17±0.05 in Fucus vesiculosus from the west coast of Ireland demonstrates the increasing significance of Sellafield-derived plutonium in those waters.

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3. 3

   Kim, S.-H.; Lee, S.-H.; Lee, H.-M.; Hong, G.-H. Distribution of 239,240Pu in Marine Products from the Seas around the Korean Peninsula after the Fukushima Nuclear Power Plant Accident. J. Environ. Radioact. 2020, 217, 106191  DOI: 10.1016/j.jenvrad.2020.106191

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   3

   Distribution of 239,240Pu in marine products from the seas around the Korean Peninsula after the Fukushima nuclear power plant accident

   Kim, Suk-Hyun; Lee, Sang-Han; Lee, Hyun-Mi; Hong, Gi-Hoon

   Journal of Environmental Radioactivity (2020), 217 (), 106191CODEN: JERAEE; ISSN:0265-931X. (Elsevier Ltd.)

   In March 2011, an earthquake caused the shutdown of the active reactors at the Fukushima Daiichi Nuclear Power Plant (NPP), with the succeeding tsunami resulting in the release of radioactively contaminated water into the adjacent Japanese coastal waters. Marine biota selected from various trophic levels were collected in Korean coastal waters throughout 2014 and 2015 and their plutonium levels were measured to evaluate the radioactive contamination levels in the marine organisms that constitute the primary seafood diet in the Republic of Korea (ROK). The results showed that the activity concns. of 239,240Pu in plankton, macroalgae, mollusks, crustaceans, and cephalopods ranged from 13 to 58, 0.64 to 0.80, 0.94 to 5.40, 0.06 to 0.50, and 0.26 mBq kg-1 of wet wt. (w.w.), resp. The activity concns. of 239,240Pu measured in the muscles of fish varied from 0.09 to 0.30 mBq kg-1 (w.w.), relatively low values compared to those in other groups regardless of fish species, size, and sampling area. The concn. characteristics of 239,240Pu in the various organs in the resp. marine products revealed that the internal organs showed higher concns. than the muscle or skin (or exoskeleton). The highest concn. of 239,240Pu was measured in the viscera of an abalone, which had an activity concn. of 6.31 mBq kg-1 (w.w.).

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4. 4

   Khandaker, M. U.; Wahib, N. B.; Amin, Y. M.; Bradley, D. A. Committed Effective Dose from Naturally Occuring Radionuclides in Shellfish. Radiat. Phys. Chem. 2013, 88, 1– 6,  DOI: 10.1016/j.radphyschem.2013.02.034

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   Committed effective dose from naturally occurring radionuclides in shellfish

   Khandaker, Mayeen Uddin; Wahib, Norfadira Binti; Amin, Yusoff Mohd.; Bradley, D. A.

   Radiation Physics and Chemistry (2013), 88 (), 1-6CODEN: RPCHDM; ISSN:0969-806X. (Elsevier B. V.)

   Recognizing their importance in the av. Malaysian daily diet, the radioactivity concns. in mollusc- and crustacean-based food have been detd. for key naturally occurring radionuclides. Fresh samples collected from various maritime locations around peninsular Malaysia have been processed using std. procedures; the radionuclide concns. being detd. using an HPGe γ-ray spectrometer. For molluscs, assuming secular equil., the range of activities of 238U (226Ra), 232Th (228Ra) and 40K were found to be 3.28±0.35 to 5.34±0.52, 1.20±0.21 to 2.44±0.21 and 118±6 to 281±14 Bq kg-1 dry wt., resp. The resp. values for crustaceans were 3.02±0.57 to 4.70±0.52, 1.38±0.21 to 2.40±0.35 and 216±11 to 316±15 Bq kg-1. The estd. av. daily intake of radioactivity from consumption of molluscs are 0.37 Bq kg-1 for 238U (226Ra), 0.16 Bq kg-1 for 232Th (228Ra) and 18 Bq kg-1 for 40K; the resp. daily intake values from crustaceans are 0.36 Bq kg-1, 0.16 Bq kg-1 and 23 Bq kg-1. Assocd. annual committed EDs from molluscs are estd. to be in the range 21.3 to 34.7 μSv for 226Ra, 19.3 to 39.1 μSv for 228Ra and 17.0 to 40.4 μSv for 40K. For crustaceans, the resp. dose ranges are 19.6 to 30.5 μSv, 22.0 to 38.4 μSv and 31.1 to 45.5 μSv, being some several times world av. values.

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5. 5

   Guillaume, T.; Chawla, F.; Steinmann, P.; Gobat, J. M.; Froidevaux, P. Disparity in 90Sr and 137Cs Uptake in Alpine Plants: Phylogenetic Effect and Ca and K Availability. Plant Soil 2012, 355, 29– 39,  DOI: 10.1007/s11104-011-1110-6

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   Disparity in 90Sr and 137Cs uptake in Alpine plants: phylogenetic effect and Ca and K availability

   Guillaume, Thomas; Chawla, Fabienne; Steinmann, Philipp; Gobat, Jean-Michel; Froidevaux, Pascal

   Plant and Soil (2012), 355 (1-2), 29-39CODEN: PLSOA2; ISSN:0032-079X. (Springer)

   Uptake of 90Sr and 137Cs in plants varies widely between soil types and between plant species. It is now recognized that the radionuclide uptake in plants is more influenced by site-specific and plant-specific parameters rather than the bulk radionuclide concn. in soil. It was hypothesized that the stress which Alpine plants experience because of the short growing season may enhance the phylogenetic effect on the 137Cs and 90Sr transfer factors as well as the dependency of the uptake by plant to the concns. of exchangeable Ca and K of soils. A field study was carried out on the 90Sr and 137Cs uptake by 11 species of Alpine plants growing on 6 undisturbed and geochem. different soils in the Alpine valley of Piora, Switzerland. Results show that a strong correlation exists between the log TF and the log of exchangeable Ca or K of the soils. Cs uptake by Phleum rhaeticum (Poales) and Alchemilla xanthochlora (Rosales) is more sensitive to the amt. of exchangeable K in the soil than the corresponding uptake by other orders. Moreover, the 90Sr results indicate a phylogenetic effect between Non-Eudicot and Eudicots: the order Poales (Phleum rhaeticum) concg. much less 90Sr than Eudicots do.

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6. 6

   Jeffree, R. A.; Oberhaensli, F.; Teyssie, J. L. Marine Radionuclide Transfer Factors in Chordates and a Phylogenetic Hypothesis. J. Environ. Radioact. 2013, 126, 388– 398,  DOI: 10.1016/j.jenvrad.2012.06.002

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   Marine radionuclide transfer factors in chordates and a phylogenetic hypothesis

   Jeffree, Ross A.; Oberhaensli, Francois; Teyssie, Jean-Louis

   Journal of Environmental Radioactivity (2013), 126 (), 388-398CODEN: JERAEE; ISSN:0265-931X. (Elsevier Ltd.)

   Previous radiotracer expts. that compared multi-elemental whole organism: water transfer factors among chondrichthyan and teleost fishes, including an ICRP ref. flatfish Psetta maxima, demonstrated distinctive contrasts in their bioaccumulation characteristics, with generally elevated bioaccumulation in chondrichthyans. These results supported a hypothesis that phylogenetic divergence may influence marine radionuclide transfer factors. This notion has been further evaluated in an amphioxus species Branchiostoma lanceolatum, sub-phylum Cephalochordata. This taxon diverged about 800 MYBP from a common ancestor of the teleosts and the chondrichthyans, which in turn diverged from each other around 500 MYBP. Our exptl. results indicate that amphioxus is indeed more divergent in its multi-elemental bioaccumulation patterns from teleosts and chondrichthyans than they are from each other, consistent with our hypothesis. The exptl. comparisons with the ICRP ref. flatfish P. maxima also revealed an unexpectedly enhanced capacity in amphioxus to accumulate all eight tested trace elements from seawater, and for some by more than two orders of magnitude. These results have practical applications for the strategic selection of marine biota for further radioecol. investigations to better guarantee the radiol. protection of marine biodiversity. Such seemingly anomalous results for understudied biota like amphioxus and chondrichthyans suggest that more effort in marine radioecol. be directed to assessing the bioaccumulatory capacities of other phylogenetic groups that have received less attention so far, particularly those that are phylogenetically more remote from commonly investigated taxa and those nominated as ICRP marine ref. organisms.

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7. 7

   Mitchell, P. I.; Downes, A. B.; Vintró, L. L.; McMahon, C. A. Studies of the Speciation, Colloidal Association and Remobilisation of Plutonium in the Marine Environment. Radioact. Environ. 2001, 1, 175– 200,  DOI: 10.1016/S1569-4860(01)80014-0

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   Studies of the speciation, colloidal association and remobilization of plutonium in the marine environment

   Mitchell, Peter I.; Downes, Anne B.; Vintro, Luis Leon; McMahon, Ciara A.

   Radioactivity in the Environment (2001), 1 (Plutonium in the Environment), 175-200CODEN: REANCK ISSN:. (Elsevier Science Ltd.)

   A review, with many refs., includes physico-chem. speciation of Pu in diverse marine environments such as the Irish Sea, the English Channel, the Mediterranean and the high Arctic. Emphasis is given to the oxidn.-state distribution of Pu in the water column and to the proportion of Pu in colloidal form. The seabed sediment compartment is also examd. and the capacity for Pu to be remobilized from sediments demonstrated by ref. to recent studies carried out in the Irish Sea. Specifically, the development of a low-resoln. compartmental model for the prediction of future Pu concns. in seawater and sediment in the Irish Sea is discussed and interpreted in terms of the processes controlling the desorption, remobilization and dispersion of Pu in this zone. The requirement to quantify its speciation locally and to identify the key processes involved in its transfer, before attempting to conceptualize a model, is stressed. The value of the modeling approach in predicting long-term trends in Pu and estg. likely mean availability times is highlighted. The forms in and extent to which Pu can be advected over large distances in the marine environment are discussed in the context of a case study of current interest.

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8. 8

   Howard, B. J.; Beresford, N. A.; Copplestone, D.; Telleria, D.; Proehl, G.; Fesenko, S.; Jeffree, R. A.; Yankovich, T. L.; Brown, J. E.; Higley, K.; Johansen, M. P.; Mulye, H.; Vandenhove, H.; Gashchak, S.; Wood, M. D.; Takata, H.; Andersson, P.; Dale, P.; Ryan, J.; Bollhöfer, A.; Doering, C.; Barnett, C. L.; Wells, C. The IAEA Handbook on Radionuclide Transfer to Wildlife. J. Environ. Radioact. 2013, 121, 55– 74,  DOI: 10.1016/j.jenvrad.2012.01.027

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   8

   The IAEA handbook on radionuclide transfer to wildlife

   Howard, B. J.; Beresford, N. A.; Copplestone, D.; Telleria, D.; Proehl, G.; Fesenko, S.; Jeffree, R. A.; Yankovich, T. L.; Brown, J. E.; Higley, K.; Johansen, M. P.; Mulye, H.; Vandenhove, H.; Gashchak, S.; Wood, M. D.; Takata, H.; Andersson, P.; Dale, P.; Ryan, J.; Bollhofer, A.; Doering, C.; Barnett, C. L.; Wells, C.

   Journal of Environmental Radioactivity (2013), 121 (), 55-74CODEN: JERAEE; ISSN:0265-931X. (Elsevier Ltd.)

   A review. An IAEA handbook presenting transfer parameter values for wildlife has recently been produced. Concn. ratios (CRwo-media) between the whole organism (fresh wt.) and either soil (dry wt.) or water were collated for a range of wildlife groups (classified taxonomically and by feeding strategy) in terrestrial, freshwater, marine and brackish generic ecosystems. The data have been compiled in an on line database, which will continue to be updated in the future providing the basis for subsequent revision of the Wildlife TRS values. An overview of the compilation and anal., and discussion of the extent and limitations of the data is presented. Example comparisons of the CRwo-media values are given for polonium across all wildlife groups and ecosystems and for molluscs for all radionuclides. The CRwo-media values have also been compared with those currently used in the ERICA Tool which represented the most complete published database for wildlife transfer values prior to this work. The use of CRwo-media values is a pragmatic approach to predicting radionuclide activity concns. in wildlife and is similar to that used for screening assessments for the human food chain. The CRwo-media values are most suitable for a screening application where there are several conservative assumptions built into the models which will, to varying extents, compensate for the variable data quality and quantity, and assocd. uncertainty.

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9. 9

   Carroll, J.; Harms, I. H. Uncertainty Analysis of Partition Coefficients in a Radionuclide Transport Model. Water Res. 1999, 33, 2617– 2626,  DOI: 10.1016/S0043-1354(99)00114-1

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   Uncertainty analysis of partition coefficients in a radionuclide transport model

   Carroll, Jolynn; Harms, Ingo H.

   Water Research (1999), 33 (11), 2617-2626CODEN: WATRAG; ISSN:0043-1354. (Elsevier Science Ltd.)

   Models of transport and pollutant dispersion are routinely used to define risks posed by contaminants present in aquatic environments. Modelers frequently utilize a simple parameter, known as a partition coeff., to apportion contaminant concns. between dissolved and particulate phases. But the inherent uncertainty in the master variables for partition coeffs. (distribution coeff. (Kd); particulate matter concn.) is also a source of uncertainty in model results. We demonstrate an approach that can be used to quantify this source of uncertainty and apply it to an investigation of the transport of radionuclides away from a radioactive waste site in a shallow Arctic Bay. Our investigation considers the radionuclides, americium, plutonium, europium, ruthenium, cobalt, cesium, and strontium which exhibit a broad range of affinities for marine particles. Probability distribution functions were constructed for radionuclide distribution coeffs. (Kd) and particulate matter concns. using Beta-Pert functions. Simulations using Latin Hypercube sampling were performed on the functions of Kd and particulate matter to define probability functions of partition coeffs. for each radionuclide. These distributions were used in a hydrodynamic model of Abrosimov Bay to predict ranges of radionuclide concns. for different atm. forcing events. From this investigation, partition coeffs. values (PCw) exhibit the highest uncertainty for radionuclides having mid-range Kd values (Kd = 1-30 m3/kg). When applied to model simulations of radionuclide transport, concns. of less particle-reactive radionuclides, strontium (Kd = 0.01 m3/kg) and cesium (Kd = 0.3 m3/kg), are most sensitive to variations in wind direction and hence to water exchange rates. Whereas europium (Kd = 100 m3/kg), ruthenium (Kd = 30 m3/kg) and cobalt (Kd = 1 m3/kg) concns. exhibit large variations in response to different combinations of partition coeff. values and wind events. Even high Kd radionuclides such as americium (Kd = 1000 m3/kg) exhibit large uncertainties in dissolved concn. when simulating low sediment concns. for the bay. Generalizing these findings, the uncertainty in the master variables used to calc. partition coeffs. is significant for all but the most sol. contaminants. The method described in this paper can be a useful tool in radionuclide transport modeling for quantifying this uncertainty.

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10. 10

    Fisher, N. S.; Fowler, S. W.; Boisson, F.; Carroll, J.; Rissanen, K.; Salbu, B.; Sazykina, T. G.; Sjoeblom, K. L. Radionuclide Bioconcentration Factors and Sediment Partition Coefficients in Arctic Seas Subject to Contamination from Dumped Nuclear Wastes. Environ. Sci. Technol. 1999, 33, 1979– 1982,  DOI: 10.1021/es9812195

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    10

    Radionuclide Bioconcentration Factors and Sediment Partition Coefficients in Arctic Seas Subject to Contamination from Dumped Nuclear Wastes

    Fisher, Nicholas S.; Fowler, Scott W.; Boisson, Florence; Carroll, JoLynn; Rissanen, Kristina; Salbu, Britt; Sazykina, Tatiana G.; Sjoeblom, Kirsti-Liisa

    Environmental Science and Technology (1999), 33 (12), 1979-1982CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)

    The disposal of large quantities of radioactive wastes in Arctic Seas by the former Soviet Union has prompted interest in the behavior of long-lived radionuclides in polar waters. Previous studies on the interactions of radionuclides prominent in radioactive wastes have focused on temperate waters; the extent to which the bioconcn. factors and sediment partitioning from these earlier studies could be applied to risk assessment analyses involving high latitude systems is unknown. We present concns. in seawater and calcd. in situ bioconcn. factors for 90Sr, 137Cs, and 239+240Pu (the 3 most important radionuclides in Arctic risk assessment models) in macroalgae, crustaceans, bivalve mollusks, sea birds, and marine mammals as well as sediment Kd values for 13 radionuclides and other elements in samples taken from the Kara and Barents Seas. Our data anal. shows that, typically, values for polar and temperate waters are comparable, but exceptions include 10-fold higher concn. factors for 239+240Pu in Arctic brown macroalgae, 10-fold lower Kd values for 90Sr in Kara Sea sediment than in typical temperate coastal sediment, and 100-fold greater Ru Kd values in Kara Sea sediment. For most elements application of temperate water bioconcn. factors and Kd values to Arctic marine systems appears to be valid.

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11. 11

    Gil-García, C.; Tagami, K.; Uchida, S.; Rigol, A.; Vidal, M. New Best Estimates for Radionuclide Solid-Liquid Distribution Coefficients in Soils. Part 3: Miscellany of Radionuclides (Cd, Co, Ni, Zn, I, Se, Sb, Pu, Am, and Others). J. Environ. Radioact. 2009, 100, 704– 715,  DOI: 10.1016/j.jenvrad.2008.12.001

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    11

    New best estimates for radionuclide solid-liquid distribution coefficients in soils. Part 3: miscellany of radionuclides (Cd, Co, Ni, Zn, I, Se, Sb, Pu, Am, and others)

    Gil-Garcia, C.; Tagami, K.; Uchida, S.; Rigol, A.; Vidal, M.

    Journal of Environmental Radioactivity (2009), 100 (9), 704-715CODEN: JERAEE; ISSN:0265-931X. (Elsevier Ltd.)

    New best ests. for the solid-liq. distribution coeff. (Kd) for a set of radionuclides are proposed, based on a selective data search and subsequent calcn. of geometric means. The Kd best ests. are calcd. for soils grouped according to the texture and org. matter content. For a limited no. of radionuclides this is extended to consider soil cofactors affecting soil-radionuclide interaction, such as pH, org. matter content, and radionuclide chem. speciation. Correlations between main soil properties and radionuclide Kd are examd. to complete the information derived from the best ests. with a rough prediction of Kd based on soil parameters. Although there are still gaps for many radionuclides, new data from recent studies improve the calcn. of Kd best ests. for a no. of radionuclides, such as selenium, antimony, and iodine.

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12. 12

    McDonald, P.; i Batlle, J. V.; Bousher, A.; Whittall, A.; Chambers, N. The Availability of Plutonium and Americium in Irish Sea Sediments for Re-Dissolution. Sci. Total Environ. 2001, 267, 109– 123,  DOI: 10.1016/S0048-9697(00)00771-3

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    12

    The availability of plutonium and americium in Irish Sea sediments for re-dissolution

    McDonald, P.; Vives i Batlle, J.; Bousher, A.; Whittall, A.; Chambers, N.

    Science of the Total Environment (2001), 267 (1-3), 109-123CODEN: STENDL; ISSN:0048-9697. (Elsevier Science Ireland Ltd.)

    The availability of Pu and Am, for re-dissoln. from offshore sediments into Irish Sea water, was examd. Sediments collected from the mud-patch near the Cumbrian coast were characterized in terms of spatial location, particle size, partitioning of radionuclides with respect to physico-chem. bonds and availability of actinides for release into seawater. Sequential extn. investigations revealed that Pu was predominantly assocd. with strongly bound sesquioxide and org. complex fractions. Am was assocd. mainly with the org. complex fraction, but a significant fraction was in carbonate form. Sediment/water re-dissoln. expts. with and without stirring were compared to simulate the effect of disturbing bed sediment. After 1 wk, neither set of re-dissoln. data provided significant trends between dissolved activity and time. Stirred systems appeared to release 2.5 times more Pu and Am into seawater than unstirred systems. Measured 239,240Pu and 241Am distribution coeffs. (Kd values) were both typically ∼105 L/Kg. 241Am Kd values are an order of magnitude lower than previously reported for the north-eastern Irish Sea, but similar to western Irish Sea values. Overall, the fractions of Pu and Am available for re-dissoln. from bed sediment are very low at <0.1%, with proportionally more Pu being released than Am. These findings lend further support for the extrapolation of lab.-derived information to environmental conditions.

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13. 13

    Swift, D. J.; Nicholson, M. D. Variability in the Edible Fraction Content of 60Co, 99Tc, 110mAg, 137Cs and 241Am between Individual Crabs and Lobsters from Sellafield (North Eastern Irish Sea). J. Environ. Radioact. 2001, 54, 311– 326,  DOI: 10.1016/S0265-931X(00)00132-6

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    13

    Variability in the edible fraction content of 60Co, 99Tc, 110mAg, 137Cs and 241Am between individual crabs and lobsters from Sellafield (north eastern Irish Sea)

    Swift, D. J.; Nicholson, M. D.

    Journal of Environmental Radioactivity (2001), 54 (3), 311-326CODEN: JERAEE; ISSN:0265-931X. (Elsevier Science Ltd.)

    We investigated the variability in anthropogenic radionuclide content of the edible fractions of individual edible crabs (Cancer pagurus L.) and European lobsters (Homarus gammarus L.) caught com. in the Sellafield offshore area. Sixteen female and 18 male crabs and 20 female and 17 male lobsters were selected from com. catches made between 25 May and 5 June 1997. Each gender group was selected to be within the known wt. range for com. caught crustacea from the area. Four artificial radionuclides (60Co, 110mAg, 137Cs or 241Am) were detected by γ-spectrometry. The edible fraction content of these radionuclides between males and females for either species were not statistically significantly different. 99Tc was analyzed by chem. sepn. and β-counting. 99Tc concns. in female crabs tended to be higher (172±205 (16) Bq kg-1(wet); mean±std. deviation (n samples)) than those in males (85±58 (18) Bq kg-1 (wet)), although this was not a statistically significant difference. For both male and female crabs, 99Tc concns. tended to decrease with increasing whole live wts. For 99Tc in lobsters the picture is less clear. Female lobsters contained more activity (14800±7400 (20) Bq kg-1 (wet)) than males (7100±3900 (17) Bq kg-1 (wet)). The results were used to discuss the implications for sampling and monitoring.

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14. 14

    Tagami, K.; Uchida, S. Marine and Freshwater Concentration Ratios (CRwo-Water): Review of Japanese Data. J. Environ. Radioact. 2013, 126, 420– 426,  DOI: 10.1016/j.jenvrad.2012.06.004

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    14

    Marine and freshwater concentration ratios (CRwo-water): review of Japanese data

    Tagami, K.; Uchida, S.

    Journal of Environmental Radioactivity (2013), 126 (), 420-426CODEN: JERAEE; ISSN:0265-931X. (Elsevier Ltd.)

    A review. The water-to-organism (whole body) concn. ratio (CRwo-water), which is defined as the ratio of the concn. of a radionuclide in the biota (Bq kg-1 fresh wt.) to that in water (Bq L-1), has been used in math. models for environmental radiation protection. In the present paper, published global fallout 90Sr, 137Cs, 106Ru, 144Ce and 239+240Pu activity concn. data and stable element concn. data for Na, K, Ca, Mg, Fe, Cu and Mn for organisms living in freshwater or seawater areas in Japan were collated. The data suitable for obtaining CRwo-water values were identified. CRwo-water values of 137Cs were similar for pelagic fish, benthic fish and whitebait (immature, small fish) with resp. geometric means of 30 (range: 4.4-69), 32 (range: 15-54) and 33 (range: 13-84). The calcd. CRwo-water values of the other radionuclides and stable elements were generally similar to other previously reported values; with the exception that those for Ce were lower for marine biota and those of Cu were higher for freshwater fish.

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15. 15

    Warwick, E.; Cundy, B.; Croudace, W.; Bains, D.; Dale, A. A. The Uptake of Iron-55 by Marine Sediment, Macroalgae, and Biota Following Discharge from a Nuclear Power Station. Environ. Sci. Technol. 2001, 35, 2171– 2177,  DOI: 10.1021/es001493a

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    15

    The Uptake of Iron-55 by Marine Sediment, Macroalgae, and Biota Following Discharge from a Nuclear Power Station

    Warwick, P. E.; Cundy, A. B.; Croudace, I. W.; Bains, M. E. D.; Dale, A. A.

    Environmental Science and Technology (2001), 35 (11), 2171-2177CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)

    Significant quantities of 55Fe, an activation product of stable iron, have been released into the environment following the atm. testing of nuclear weapons (mainly in the 1950s and 1960s) as well as through authorized discharges of radioactivity from nuclear power and reprocessing sites. Although some studies have been performed on the behavior of weapons' fallout-derived 55Fe in the environment and subsequent impact on humans, little has been published on the behavior of 55Fe released as a point source discharge from nuclear sites. This study presents data on the concn. and temporal variation of 55Fe in fucoid seaweeds, shellfish, crab, and lobster collected from Weymouth Bay and adjacent coastal areas, southern England. These areas have received authorized discharges of radionuclides originating from the operation of a now-decommissioned steam-generating, heavy water-type reactor at AEE Winfrith. The highest activities of 55Fe are found assocd. with marine sediments collected near the discharge pipeline and a rapid decline occurs away from the pipeline. This is consistent with rapid sorption of 55Fe by the sediment, and the data show there is only limited reworking and remobilization. Activities of 55Fe in biota generally decreased over time, due to a redn. in the amt. of 55Fe discharged. The variation of 55Fe activity, revealed from the monthly sampling of seaweed, does not reflect the short-term fluctuations seen in the patterns of discharged 55Fe activity. Although discharges of 55Fe from AEE Winfrith exceeded other radionuclides, the radiol. impact on local seafood consumers is considerably less than for other key radionuclides such as 60Co and 65Zn but of comparable magnitude to the global av. population dose arising from fallout-derived 55Fe.

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16. 16

    Hooda, P. S.; Zhang, H.; Davison, W.; Edwards, A. C. Measuring Bioavailable Trace Metals by Diffusive Gradients in Thin Films (DGT): Soil Moisture Effects on Its Performance in Soils. Eur. J. Soil Sci. 1999, 50, 285– 294,  DOI: 10.1046/j.1365-2389.1999.00226.x

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    16

    Measuring bioavailable trace metals by diffusive gradients in thin films (DGT): soil moisture effects on its performance in soils

    Hooda, P. S.; Zhang, H.; Davison, W.; Edwards, A. C.

    European Journal of Soil Science (1999), 50 (2), 285-294CODEN: ESOSES; ISSN:1351-0754. (Blackwell Science Ltd.)

    Conventional methods of measuring labile chem. species of trace metals in soil solns., such as chem. competition following centrifuging, are inadequate if the speciation changes during sampling and extn. A new technique, diffusive gradients in thin films (DGT), measures labile species of trace metals in natural waters and sediments in situ. A well-defined diffusive gel layer distinguishes it from other resin-based techniques. It perturbs the soil in a controlled way by introducing an in situ local sink for metal ions. Resulting fluxes to the device are quant. measured, allowing assessment of resupply kinetics and in some cases measurement of in situ soil soln. concns. We used DGT to measure fluxes of Cd, Co, Cu, Ni, Pb and Zn in a sludge-treated soil at various moisture contents (27-106%). Replicate measurements showed that the precision of DGT-measured fluxes was within 10%. For moisture contents exceeding the field capacity (42%), the DGT response reflected soil water concns. At smaller moisture contents, changes related to tortuosity and diln. were reflected in the measurements. This technique has the potential for in situ measurements in the field where it should provide quant. flux data on individual soils and provide a good surrogate for bioavailable metal.

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17. 17

    Zhang, H.; Davison, W. Use of Diffusive Gradients in Thin-Films for Studies of Chemical Speciation and Bioavailability. Environ. Chem. 2015, 12, 85– 101,  DOI: 10.1071/EN14105

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    17

    Use of diffusive gradients in thin-films for studies of chemical speciation and bioavailability

    Zhang, Hao; Davison, William

    Environmental Chemistry (2015), 12 (2), 85-101CODEN: ECNHAA; ISSN:1449-8979. (CSIRO Publishing)

    Environmental context The health of aquatic organisms depends on the distribution of the dissolved forms of chem. components (speciation) and their rates of interaction (dynamics). This review documents and explains progress made using the dynamic technique of diffusive gradients in thin-films (DGT) to meet these challenges of measuring directly chem. speciation and assocd. dynamics in natural waters. The relevance of these measurements to uptake by biota of chem. forms in soils, sediments and water is discussed with ref. to this expanding literature. Abstr. This review assesses progress in studies of chem. speciation using diffusive gradients in thin-films (DGT) by examg. the contributions made by key publications in the last 20 years. The theor. appreciation of the dynamic soln. components measured by DGT has provided an understanding of how DGT measures most metal complexes, but excludes most colloids. These findings strengthen the use of DGT as a monitoring tool and provide a framework for using DGT to obtain in situ kinetic information. Generally, the capabilities of DGT as an in situ perturbation and measurement tool have yet to be fully exploited. Studies that have used DGT to investigate processes relevant to bioavailability have blossomed in the last 10 years, esp. for soils, as DGT mimics the diffusion limiting uptake conditions that, under some conditions, characterize uptake by plants. As relationships between element accumulated by DGT and in plants depend on the plant species, soils studied, and the element and its chem. form, DGT is not an infallible predictive tool. Rather its strength comes from providing information on the labile species in the system, whether water, soil or sediment. Recent studies have shown good relationships between measurements of metals in periphyton and by DGT, and unified dose response curves have been obtained for biota in sediments when they are based on DGT measurements. Both these cases suggest that alternative approaches to the established 'free ion' approach may be fruitful in these media and illustrate the growing use of DGT to investigate environmental chem. processes.

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18. 18

    Zhang, C.; Ding, S.; Xu, D.; Tang, Y.; Wong, M. H. Bioavailability Assessment of Phosphorus and Metals in Soils and Sediments: A Review of Diffusive Gradients in Thin Films (DGT). Environ. Monit. Assess. 2014, 186, 7367– 7378,  DOI: 10.1007/s10661-014-3933-0

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    18

    Bioavailability assessment of phosphorus and metals in soils and sediments: a review of diffusive gradients in thin films (DGT)

    Zhang, Chaosheng; Ding, Shiming; Xu, Di; Tang, Ya; Wong, Ming H.

    Environmental Monitoring and Assessment (2014), 186 (11), 7367-7378CODEN: EMASDH; ISSN:0167-6369. (Springer)

    A review. This paper provides an overview of the principle and latest development of the diffusive gradients in thin films (DGT) technol. and its applications in environmental studies with a focus on bioavailability assessment of phosphorus and metals in sediments and soils. Compared with conventional methods, DGT, as a passive sampling method, has significant advantages: in situ measurement, time averaged concns. and high spatial resoln. The in situ measurement avoids artificial influences including contamination of samples and sample treatment which may change the forms of chems. The time averaged concn. reflects representative measurement over a period of time. The high-resoln. information captures the biogeochem. heterogeneity of elements of interest distributed in microenvironments, such as in the rhizosphere and the vicinity of the sediment-water interface. Moreover, DGT is a dynamic technique which simultaneously considers the diffusion of solutes and their kinetic resupply from the solid phases. All the advantages of DGT significantly promote the collection of "true" information of the bioavailable or labile forms of chems. in the environment. DGT provides potential for applications in agriculture, environmental monitoring and the mining industry. However, the applications are still at the early testing stage. Further studies are needed to properly interpret the DGT-measured results under complex environmental conditions, and std. procedures and guideline values based on DGT are required to pave the way for its routine applications in environmental monitoring.

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19. 19

    Philipps, R. R.; Xu, X.; Mills, G. L.; Bringolf, R. B. Evaluation of Diffusive Gradients in Thin Films for Prediction of Copper Bioaccumulation by Yellow Lampmussel (Lampsilis Cariosa) and Fathead Minnow (Pimephales Promelas). Environ. Toxicol. Chem. 2018, 37, 1535– 1544,  DOI: 10.1002/etc.4108

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    19

    Evaluation of diffusive gradients in thin films for prediction of copper bioaccumulation by yellow lampmussel (Lampsilis cariosa) and fathead minnow (Pimephales promelas)

    Philipps, Rebecca R.; Xu, Xiaoyu; Mills, Gary L.; Bringolf, Robert B.

    Environmental Toxicology and Chemistry (2018), 37 (6), 1535-1544CODEN: ETOCDK; ISSN:0730-7268. (Wiley-Blackwell)

    Using a coupled method of diffusive gradients in thin films (DGT) exposure with aquatic organism bioassays, the authors assessed the use of DGT as a tool for estg. copper (Cu) bioavailability in contaminated waters. The DGT-accumulated Cu fraction could possibly be used as a surrogate for other assessments of metal bioavailability. The Cu concns. in fathead minnow (Pimephales promelas) and yellow lampmussel (Lampsilis cariosa) soft tissue were compared with DGT-accumulated Cu after 2, 4, and 6 d of exposure to a Cu concn. series in static, water-only assays. The DGT-accumulated Cu was found to include free Cu ions, labile inorg. Cu complexes, and labile dissolved org. matter Cu complexes, compared with Cu speciation output from the biotic ligand model. Regressions of Cu concns. between DGT and fathead minnow at 4 and 6 d of exposure demonstrated linear relationships. The Cu bioaccumulated in yellow lampmussel was overpredicted by DGT at Cu concns. greater than 10 μg L-1, which may be caused by internal regulation of Cu. The speciation component of the biotic ligand model predicted relationships between inorg. Cu and animal-accumulated Cu that were similar to predicted relationships between DGT-indicated Cu and animal-accumulated Cu at all deployment durations. Environ Toxicol Chem 2018;9999:1-10. © 2018 SETAC.

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20. 20

    Hutchins, C. M.; Panther, J. G.; Teasdale, P. R.; Wang, F.; Stewart, R. R.; Bennett, W. W.; Zhao, H. Evaluation of a Titanium Dioxide-Based DGT Technique for Measuring Inorganic Uranium Species in Fresh and Marine Waters. Talanta 2012, 97, 550– 556,  DOI: 10.1016/j.talanta.2012.05.012

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    20

    Evaluation of a titanium dioxide-based DGT technique for measuring inorganic uranium species in fresh and marine waters

    Hutchins, Colin M.; Panther, Jared G.; Teasdale, Peter R.; Wang, Feiyue; Stewart, Ryan R.; Bennett, William W.; Zhao, Huijun

    Talanta (2012), 97 (), 550-556CODEN: TLNTA2; ISSN:0039-9140. (Elsevier B.V.)

    A new diffusive gradients in a thin film (DGT) technique for measuring dissolved U in freshwater is reported. The new method utilizes a previously described binding phase, Metsorb (a titania-based adsorbent). This binding phase was evaluated and compared to the well-established Chelex-DGT method. Batch expts. showed quant. uptake (100±3%) of dissolved U by Metsorb and an elution efficiency of 95% was obtained using a mixed eluent of 1 mol/L NaOH/1 mol/L H2O2. The mass of U accumulated by Metsorb was linear (R2 ≥0.98) with time across the pH 3.0-8.1, validating the DGT measurement. The measured effective diffusion coeffs. were highly dependent on pH, 2.74-4.81 × 10-6 cm2/s, which were in reasonable agreement with values from the literature. Ionic strength showed no effect on the uptake of U, and thereby on diffusion coeffs., at NaNO3 concns. ≤0.01 mol/L, but caused the U concn. to be underestimated by 18 and 24% at 0.1 mol/L NaNO3 and 0.7 mol/L NaNO3, resp. Deployment of Metsorb-DGT in synthetic freshwater resulted in reliable measurement of the dissolved U concn. (CDGT/CSol =1.05), whereas Chelex-DGT significantly underestimated the dissolved U concn. (CDGT/CSol =0.76). Metsorb-DGT gave reliable results after 8 h deployments in synthetic seawater but experienced competition effects with longer deployments. The Chelex-DGT was unable to measure U at all in synthetic seawater. A field deployment in a freshwater stream (Coomera River) confirmed the utility of the Metsorb-DGT method for measuring U in natural freshwaters, but performance of field deployments may require further evaluation due to the possibility of major changes in U speciation with pH and water compn. We recommend a filtered sample, of any water in which DGT measurements are to be made, be used to det. the appropriate diffusion coeff. under controlled lab. conditions.

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21. 21

    Turner, G. S. C.; Mills, G. A.; Bowes, M. J.; Burnett, J. L.; Amos, S.; Fones, G. R. Evaluation of DGT as a Long-Term Water Quality Monitoring Tool in Natural Waters; Uranium as a Case Study. Environ. Sci. Process. Impacts 2014, 16, 393– 403,  DOI: 10.1039/c3em00574g

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    21

    Evaluation of DGT as a long-term water quality monitoring tool in natural waters; uranium as a case study

    Turner, Geraldine S. C.; Mills, Graham A.; Bowes, Michael J.; Burnett, Jonathan L.; Amos, Sean; Fones, Gary R.

    Environmental Science: Processes & Impacts (2014), 16 (3), 393-403CODEN: ESPICZ; ISSN:2050-7895. (Royal Society of Chemistry)

    The performance of the diffusive gradient in thin film technique (DGT) was evaluated as a tool for the long-term monitoring of water quality, using uranium as a case study. DGTs with a Metsorb® (TiO2) sorbent were deployed consecutively at two alk. freshwater sites, the River Enborne and the River Lambourn, UK for seven-day intervals over a five-month deployment period to obtain time weighted av. concns. Weekly spot samples were taken to det. phys. and chem. properties of the river water. Uranium was measured in these spot samples and after extn. from the DGT devices. The accuracy of the DGT device time weighted av. concns. to averaged spot water samples in both rivers was 86% (27 to 205%). The DGT diffusive boundary layer (DBL) (0.037-0.141 cm - River Enborne and 0.062-0.086 cm - River Lambourn) was affected by both water flow and biofouling of the diffusion surface. DBL thicknesses found at both sites were correlated with flow conditions with an R2 value of 0.614. Correlations were also obsd. between the DBL thickness and dissolved org. carbon (R2 = 0.637) in the River Lambourn, indicating the potential presence of a complex zone of chem. interactions at the surface of the DGT. The range of DBL thicknesses found at the River Lambourn site were also attributed to of the development of macro-flora on the active sampling surface, indicating that the DBL thickness cannot be assumed to be water flow dependant only. Up to a 57% under-est. of uranium DGT concn. was obsd. compared to spot sample concns. if the DBL was neglected. This study has shown that the use of DGT can provide valuable information in environmental monitoring schemes as part of a 'tool-box' approach when used alongside conventional spot sampling methods.

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22. 22

    Turner, G. S. C.; Mills, G.; Teasdale, P. R.; Burnett, J. L.; Amos, S.; Fones, G. R. Evaluation of DGT Techniques for Measuring Inorganic Uranium Species in Natural Waters: Interferences, Deployment Time and Speciation. Anal. Chim. Acta 2012, 739, 37– 46,  DOI: 10.1016/j.aca.2012.06.011

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    22

    Evaluation of DGT techniques for measuring inorganic uranium species in natural waters: Interferences, deployment time and speciation

    Turner, Geraldine S. C.; Mills, Graham A.; Teasdale, Peter R.; Burnett, Jonathan L.; Amos, Sean; Fones, Gary R.

    Analytica Chimica Acta (2012), 739 (), 37-46CODEN: ACACAM; ISSN:0003-2670. (Elsevier B.V.)

    Three adsorbents (Chelex-100, MnO2 and Metsorb), used as binding layers with the diffusive gradient in thin film (DGT) technique, were evaluated for the measurement of inorg. U species in synthetic and natural waters. U was found to be quant. accumulated in soln. (10-100 μg/L) by all 3 adsorbents (uptake efficiencies 80-99%) with elution efficiencies 80% (Chelex-100), 84% (MnO2) and 83% (Metsorb). Consistent uptake occurred over pH (5-9), with only MnO2 affected by pH <5, and ionic strength (0.001-1 mol/L NaNO3) ranges typical of natural waters, including seawater. DGT validation expts. (5 days) gave linear mass uptake over time (R2 ≥0.97) for all 3 adsorbents in low ionic strength soln. (0.01M NaNO3). Validation expts. in artificial seawater gave linear mass uptake for Metsorb (R2 ≥0.9954) ≤12 h and MnO2 (R2 ≥0.9259) ≤24 h. Chelex-100 demonstrated non linear mass uptake in artificial seawater after 8 h. Possible interferences were studied with SO42- (0.02-200 mg/L) with little effects on any of the 3 DGT binding layers. PO43- addns. (5 μg/L-5 mg/L) interfered by forming anionic uranyl phosphate complexes that Chelex-100 was unable to accumulate, or by directly competing with the uranyl species for binding sites, as with MnO2 and the Metsorb. HCO3- (0.1-500 mg/L) addns. formed anionic species which interfered with the performance of the Chelex-100 and the MnO2, and the Ca2+ (0.1-500 mg/L) had the affect of forming labile Ca uranyl species which aided uptake of U by all 3 resins. DGT field deployments in sea water (Southampton Water, UK) gave a linear mass uptake of U over time with Metsorb and MnO2 (4 days). Field deployments in fresh water (River Lambourn, UK) gave linear uptake for up to 7 and 4 days for Metsorb and MnO2, resp. Field deployment of the Metsorb-DGT samplers with various diffusive layer thicknesses (0.015-0.175 cm) allowed accurate measurements of the diffusive boundary layer (DBL) and allowed DBL cor. concns. to be detd. This DBL-cor. U concn. was half that detd. when the effect of the DBL was not considered. The ability of the DGT devices to measure U isotopic ratios with no isotopic fractionation was shown by all 3 resins, thereby proving the usefulness of the technique for environmental monitoring purposes.

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23. 23

    Cusnir, R.; Steinmann, P.; Christl, M.; Bochud, F.; Froidevaux, P. Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films. J. Vis. Exp. 2015, e53188  DOI: 10.3791/53188

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24. 24

    Cusnir, R.; Christl, M.; Steinmann, P.; Bochud, F.; Froidevaux, P. Evidence of Plutonium Bioavailability in Pristine Freshwaters of a Karst System of the Swiss Jura Mountains. Geochim. Cosmochim. Acta 2017, 206, 30– 39,  DOI: 10.1016/j.gca.2017.02.030

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    24

    Evidence of plutonium bioavailability in pristine freshwaters of a karst system of the Swiss Jura Mountains

    Cusnir, Ruslan; Christl, Marcus; Steinmann, Philipp; Bochud, Francois; Froidevaux, Pascal

    Geochimica et Cosmochimica Acta (2017), 206 (), 30-39CODEN: GCACAK; ISSN:0016-7037. (Elsevier Ltd.)

    The interaction of trace environmental plutonium with dissolved natural org. matter (NOM) plays an important role on its mobility and bioavailability in freshwater environments. Here we explore the speciation and biogeochem. behavior of Pu in freshwaters of the karst system in the Swiss Jura Mountains. Chem. extn. and ultrafiltration methods were complemented by diffusive gradients in thin films technique (DGT) to measure the dissolved and bioavailable Pu fraction in water. Accelerator mass spectrometry (AMS) was used to accurately det. Pu in this pristine environment. Selective adsorption of Pu (III, IV) on silica gel showed that 88% of Pu in the mineral water is found in +V oxidn. state, possibly in a highly sol. [PuO+2(CO3)n]m- form. Ultrafiltration expts. at 10 kDa yielded a similar fraction of colloid-bound Pu in the org.-rich and in mineral water (18-25%). We also found that the concns. of Pu measured by DGT in mineral water are similar to the bulk concn., suggesting that dissolved Pu is readily available for biouptake. Sequential elution (SE) of Pu from aquatic plants revealed important co-pptn. of potentially labile Pu (60-75%) with calcite fraction within outer compartment of the plants. Hence, we suggest that plutonium is fully available for biol. uptake in both mineral and org.-rich karstic freshwaters.

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25. 25

    Cusnir, R.; Steinmann, P.; Bochud, F.; Froidevaux, P. A DGT Technique for Plutonium Bioavailability Measurements. Environ. Sci. Technol. 2014, 48, 10829– 10834,  DOI: 10.1021/es501149v

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    25

    A DGT Technique for Plutonium Bioavailability Measurements

    Cusnir, Ruslan; Steinmann, Philipp; Bochud, Francois; Froidevaux, Pascal

    Environmental Science & Technology (2014), 48 (18), 10829-10834CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)

    The toxicity of heavy metals in natural waters is strongly dependent on the local chem. environment. Assessing the bioavailability of radionuclides predicts the toxic effects to aquatic biota. The technique of diffusive gradients in thin films (DGT) is largely exploited for bioavailability measurements of trace metals in waters. However, it has not been applied for plutonium speciation measurements yet. This study investigates the use of DGT technique for plutonium bioavailability measurements in chem. different environments. We used a diffusion cell to det. the diffusion coeffs. (D) of plutonium in polyacrylamide (PAM) gel and found D in the range of 2.06-2.29 × 10-6 cm2 s-1. It ranged between 1.10 and 2.03 × 10-6 cm2/s in the presence of fulvic acid and in natural waters with low DOM. In the presence of 20 ppm of humic acid of an org.-rich soil, plutonium diffusion was hindered by a factor of 5, with a diffusion coeff. of 0.50 × 10-6 cm2 s-1. We also tested com. available DGT devices with Chelex resin for plutonium bioavailability measurements in lab. conditions and the diffusion coeffs. agreed with those from the diffusion cell expts. These findings show that the DGT methodol. can be used to investigate the bioaccumulation of the labile plutonium fraction in aquatic biota.

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26. 26

    Cusnir, R.; Jaccard, M.; Bailat, C.; Christl, M.; Steinmann, P.; Haldimann, M.; Bochud, F.; Froidevaux, P. Probing the Kinetic Parameters of Plutonium-Naturally Occurring Organic Matter Interactions in Freshwaters Using the Diffusive Gradients in Thin Films Technique. Environ. Sci. Technol. 2016, 50, 5103– 5110,  DOI: 10.1021/acs.est.5b05435

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    26

    Probing the Kinetic Parameters of Plutonium-Naturally Occurring Organic Matter Interactions in Freshwaters Using the Diffusive Gradients in Thin Films Technique

    Cusnir, Ruslan; Jaccard, Maud; Bailat, Claude; Christl, Marcus; Steinmann, Philipp; Haldimann, Max; Bochud, Francois; Froidevaux, Pascal

    Environmental Science & Technology (2016), 50 (10), 5103-5110CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)

    The interaction of trace metals with naturally occurring org. matter (NOM) is a key process of the speciation of trace elements in aquatic environments. The rate of dissocn. of metal-NOM complexes will impact the amt. of free metal available for biouptake. Assessing the bioavailability of Pu helps to predict its toxic effects on aquatic biota. However, the rate of dissocn. of Pu-NOM complexes in natural freshwaters is currently unknown. We used the technique of diffusive gradients in thin films (DGT) with several diffusive layer thicknesses to provide new insights into the dissocn. kinetics of Pu-NOM complexes. Results show that Pu complexes with NOM (mainly fulvic acid) are somewhat labile (0.2≤ ξ ≤0.4), with kd =7.5 × 10-3/s. DGT measurements of environmental Pu in org.-rich natural water confirm these findings. We detd. the effective diffusion coeffs. of Pu(V) in polyacrylamide (PAM) gel in the presence of humic acid using a diffusion cell (D =1.70±0.25 × 10-6 cm2/s). These results show that Pu(V) is a more mobile species than Pu(IV).

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27. 27

    Hutchins, C. M.; Panther, J. G.; Teasdale, P. R.; Wang, F.; Stewart, R. R.; Bennett, W. W.; Zhao, H. Evaluation of a Titanium Dioxide-Based DGT Technique for Measuring Inorganic Uranium Species in Fresh and Marine Waters. Talanta 2012, 97, 550– 556,  DOI: 10.1016/J.TALANTA.2012.05.012

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    27

    Evaluation of a titanium dioxide-based DGT technique for measuring inorganic uranium species in fresh and marine waters

    Hutchins, Colin M.; Panther, Jared G.; Teasdale, Peter R.; Wang, Feiyue; Stewart, Ryan R.; Bennett, William W.; Zhao, Huijun

    Talanta (2012), 97 (), 550-556CODEN: TLNTA2; ISSN:0039-9140. (Elsevier B.V.)

    A new diffusive gradients in a thin film (DGT) technique for measuring dissolved U in freshwater is reported. The new method utilizes a previously described binding phase, Metsorb (a titania-based adsorbent). This binding phase was evaluated and compared to the well-established Chelex-DGT method. Batch expts. showed quant. uptake (100±3%) of dissolved U by Metsorb and an elution efficiency of 95% was obtained using a mixed eluent of 1 mol/L NaOH/1 mol/L H2O2. The mass of U accumulated by Metsorb was linear (R2 ≥0.98) with time across the pH 3.0-8.1, validating the DGT measurement. The measured effective diffusion coeffs. were highly dependent on pH, 2.74-4.81 × 10-6 cm2/s, which were in reasonable agreement with values from the literature. Ionic strength showed no effect on the uptake of U, and thereby on diffusion coeffs., at NaNO3 concns. ≤0.01 mol/L, but caused the U concn. to be underestimated by 18 and 24% at 0.1 mol/L NaNO3 and 0.7 mol/L NaNO3, resp. Deployment of Metsorb-DGT in synthetic freshwater resulted in reliable measurement of the dissolved U concn. (CDGT/CSol =1.05), whereas Chelex-DGT significantly underestimated the dissolved U concn. (CDGT/CSol =0.76). Metsorb-DGT gave reliable results after 8 h deployments in synthetic seawater but experienced competition effects with longer deployments. The Chelex-DGT was unable to measure U at all in synthetic seawater. A field deployment in a freshwater stream (Coomera River) confirmed the utility of the Metsorb-DGT method for measuring U in natural freshwaters, but performance of field deployments may require further evaluation due to the possibility of major changes in U speciation with pH and water compn. We recommend a filtered sample, of any water in which DGT measurements are to be made, be used to det. the appropriate diffusion coeff. under controlled lab. conditions.

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28. 28

    Christl, M.; Vockenhuber, C.; Kubik, P. W.; Wacker, L.; Lachner, J.; Alfimov, V.; Synal, H. A. The ETH Zurich AMS Facilities: Performance Parameters and Reference Materials. Nucl. Instrum. Methods Phys. Res., Sect. B 2013, 294, 29– 38,  DOI: 10.1016/j.nimb.2012.03.004

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    28

    The ETH Zurich AMS facilities: Performance parameters and reference materials

    Christl, M.; Vockenhuber, C.; Kubik, P. W.; Wacker, L.; Lachner, J.; Alfimov, V.; Synal, H.-A.

    Nuclear Instruments & Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms (2013), 294 (), 29-38CODEN: NIMBEU; ISSN:0168-583X. (Elsevier B.V.)

    A review. The current performance of all three AMS systems in operation at ETH Zurich, the 6 MV HVEC EN-Tandem facility "TANDEM", the 0.5 MV NEC Pelletron "TANDY", and the 0.2 MV system "MICADAS" is summarized. Radionuclides routinely measured with these AMS systems include 10Be, 14C, 26Al, 36Cl, 41Ca, 129I and the actinides. The ref. materials used for the normalization of the AMS measurements at the ETH Zurich AMS facilities are presented. This paper therefore is a comprehensive status report of all three AMS systems currently operated by the Lab. of Ion Beam Physics (LIP) at ETH Zurich and documents their performance and operation parameters.

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29. 29

    Endrizzi, F.; Rao, L. Chemical Speciation of Uranium(VI) in Marine Environments: Complexation of Calcium and Magnesium Ions with [(UO2)(CO3)3]4-and the Effect on the Extraction of Uranium from Seawater. Chem. - Eur. J. 2014, 20, 14499– 14506,  DOI: 10.1002/chem.201403262

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    29

    Chemical Speciation of Uranium(VI) in Marine Environments: Complexation of Calcium and Magnesium Ions with [(UO2)(CO3)3]4- and the Effect on the Extraction of Uranium from Seawater

    Endrizzi, Francesco; Rao, Linfeng

    Chemistry - A European Journal (2014), 20 (44), 14499-14506CODEN: CEUJED; ISSN:0947-6539. (Wiley-VCH Verlag GmbH & Co. KGaA)

    The interactions of Ca2+ and Mg2+ with [UO2(CO3)3]4- were studied by Ca ion selective electrode potentiometry and spectrophotometry. The stability consts. of ternary Ca-UO2-CO3 and Mg-UO2-CO3 complexes were detd. with Ca ion selective electrode potentiometry and optical absorption spectrophotometry, resp. The enthalpies of complexation for 2 successive complexes, [CaUO2(CO3)3]2- and [Ca2UO2(CO3)3](aq), were detd. for the 1st time by microcalorimetry. The data help to revise the speciation of U(VI) species under seawater conditions. In contrast to the previously accepted assumption that the highly neg. charged [UO2(CO3)3]4- is the dominant species, the revised speciation indicates that the dominant aq. U(VI) species under seawater conditions is the neutral [Ca2UO2(CO3)3](aq). The results have a significant impact on the strategies for developing efficient sorption processes to ext. U from seawater.

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    Manos, M. J.; Ding, N.; Kanatzidis, M. G. Layered Metal Sulfides: Exceptionally Selective Agents for Radioactive Strontium Removal. Proc. Natl. Acad. Sci. U.S.A. 2008, 105, 3696– 3699,  DOI: 10.1073/pnas.0711528105

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    30

    Layered metal sulfides: exceptionally selective agents for radioactive strontium removal

    Manos, Manolis J.; Ding, Nan; Kanatzidis, Mercouri G.

    Proceedings of the National Academy of Sciences of the United States of America (2008), 105 (10), 3696-3699CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)

    The authors report the family of robust layered sulfides K2xMnxSn3-xS6 (x = 0.5-0.95) (KMS-1). These materials feature hexagonal [MnxSn3-xS6]2x- slabs of the CdI2 type and contain highly mobile K+ ions in their interlayer space that are easily exchangeable with other cations and particularly Sr. KMS-1 display outstanding preference for Sr ions in highly alk. solns. contg. extremely large excess of Na cations as well as in acidic environment where most alternative adsorbents with O ligands are nearly inactive. The implication of these results is that simple layered sulfides should be considered for the efficient remediation of certain nuclear wastes.

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31. 31

    Manos, M. J.; Kanatzidis, M. G. Highly Efficient and Rapid Cs + Uptake by the Layered Metal Sulfide K 2xMn XSn 3-XS 6 (KMS-1). J. Am. Chem. Soc. 2009, 131, 6599– 6607,  DOI: 10.1021/ja900977p

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    31

    Highly Efficient and Rapid Cs+ Uptake by the Layered Metal Sulfide K2xMnxSn3-xS6 (KMS-1)

    Manos, Manolis J.; Kanatzidis, Mercouri G.

    Journal of the American Chemical Society (2009), 131 (18), 6599-6607CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)

    The details of the ion-exchange properties of the layered sulfide material K2xMnxSn3-xS6 (x = 0.5-0.95) (KMS-1) with Cs+ and Rb+ cations are reported. XPS, elemental analyses, and powder and single-crystal diffraction studies revealed that the Cs+ and Rb+ ion exchange of KMS-1 is complete (quant. replacement of K+ ions) and topotactic. These data also revealed that the Cs+ exchange is accompanied with a rare topotactic oxidn. of Mn2+ to Mn3+ caused by atm. oxygen, while the Rb+ ion exchange only slightly alters the oxidn. state of the layer manganese atoms. The absorption of Cs+ by KMS-1 follows the Langmuir model with a high exchange capacity of 226(4) mg/g (pH ≈ 7) and distribution coeffs. as high as 2 × 104 mL/g. KMS-1 displays significant cesium uptake both under strongly acidic (pH 0.7-2.6) or basic conditions (pH 10-12). The kinetics of Cs+ capture by KMS-1 is fast (>90% removal of ∼1 ppm of Cs+ within only 5 min). KMS-1 was also found capable to efficiently absorb Cs+ from complex solns. contg. various competitive cations in large excess. KMS-1 (contg. Mn3+ ions) can be regenerated and reused for Cs+ exchange with an exchange capacity very similar to that of the pristine KMS-1. The results indicate that layered metal sulfides with ion-exchange properties may be considered as highly selective and cost-effective sorbents for remediation of water contaminated with the radioactive 137Cs isotope. The selectivity over other alkali ions for Cs originates not from a size effect but from the more favorable Cs···S soft Lewis acid/Lewis base interactions.

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    Sengupta, P.; Dudwadkar, N. L.; Vishwanadh, B.; Pulhani, V.; Rao, R.; Tripathi, S. C.; Dey, G. K. Uptake of Hazardous Radionuclides within Layered Chalcogenide for Environmental Protection. J. Hazard. Mater. 2014, 266, 94– 101,  DOI: 10.1016/j.jhazmat.2013.12.010

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    32

    Uptake of hazardous radionuclides within layered chalcogenide for environmental protection

    Sengupta, Pranesh; Dudwadkar, N. L.; Vishwanadh, B.; Pulhani, V.; Rao, Rekha; Tripathi, S. C.; Dey, G. K.

    Journal of Hazardous Materials (2014), 266 (), 94-101CODEN: JHMAD9; ISSN:0304-3894. (Elsevier B.V.)

    Ensuring environmental protection in and around nuclear facilities is a matter of deep concern. Toward this, layered chalcogenide with CdI2 crystal structure has been prepd. Structural characterizations of layered chalcogenide suggest topotactic ionic substitution as the dominant mechanism behind uptake of different cations within its lattice structure. An equilibration time of 45 min and vol. to mass ratio of 30:1 are found to absorb 233U, 239Pu, 106Ru, 85+89Sr, 137Cs and 241Am radionuclides to the max. extents.

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33. 33

    Feng, M.-L.; Sarma, D.; Qi, X.-H.; Du, K.-Z.; Huang, X.-Y.; Kanatzidis, M. G. Efficient Removal and Recovery of Uranium by a Layered Organic-Inorganic Hybrid Thiostannate. J. Am. Chem. Soc. 2016, 138, 12578– 12585,  DOI: 10.1021/jacs.6b07351

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    33

    Efficient Removal and Recovery of Uranium by a Layered Organic-Inorganic Hybrid Thiostannate

    Feng, Mei-Ling; Sarma, Debajit; Qi, Xing-Hui; Du, Ke-Zhao; Huang, Xiao-Ying; Kanatzidis, Mercouri G.

    Journal of the American Chemical Society (2016), 138 (38), 12578-12585CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)

    Uranium is important in the nuclear fuel cycle both as an energy source and as radioactive waste. It is of vital importance to recover uranium from nuclear waste solns. for further treatment and disposal. Herein we present the first chalcogenide example, (Me2NH2)1.33(Me3NH)0.67Sn3S7· 1.25H2O (FJSM-SnS), in which org. amine cations can be used for selective UO22+ ion-exchange. The UO22+-exchange kinetics perfectly conforms to pseudo-second-order reaction, which is obsd. for the first time in a chalcogenide ion-exchanger. This reveals the chem. adsorption process and its ion-exchange mechanism. FJSM-SnS has excellent pH stability in both strongly acidic and basic environments (pH = 2.1-11), with a max. uranium-exchange capacity of 338.43 mg/g. It can efficiently capture UO22+ ions in the presence of high concns. of Na+, Ca2+, or HCO3- (the highest distribution coeff. Kd value reached 4.28 × 104 mL/g). The material is also very effective in removing of trace levels of U in the presence of excess Na+ (the relative amts. of U removed are close to 100%). The UO22+···S2- interactions are the basis for the high selectivity. Importantly, the uranyl ion in the exchanged products could be easily eluted with an environmentally friendly method, by treating the UO22+-laden materials with a concd. KCl soln. These advantages coupled with the very high loading capacity, low cost, environmentally friendly nature, and facile synthesis make FJSM-SnS a new promising remediation material for removal of radioactive U from nuclear waste solns.

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34. 34

    Qi, X.-H.; Du, K.-Z.; Feng, M.-L.; Li, J.-R.; Du, C.-F.; Zhang, B.; Huang, X.-Y. A Two-Dimensionally Microporous Thiostannate with Superior Cs+ and Sr2+ Ion-Exchange Property. J. Mater. Chem. A 2015, 3, 5665– 5673,  DOI: 10.1039/c5ta00566c

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    34

    A two-dimensionally microporous thiostannate with superior Cs+ and Sr2+ ion-exchange property

    Qi, Xing-Hui; Du, Ke-Zhao; Feng, Mei-Ling; Li, Jian-Rong; Du, Cheng-Feng; Zhang, Bo; Huang, Xiao-Ying

    Journal of Materials Chemistry A: Materials for Energy and Sustainability (2015), 3 (10), 5665-5673CODEN: JMCAET; ISSN:2050-7496. (Royal Society of Chemistry)

    The removal of highly radioactive and long-lived 137Cs+ and 90Sr2+ from soln. is of significance for radionuclide remediation. We prepd. a 2-dimensional microporous thiostannate, namely, (Me2NH2)4/3(Me3NH)2/3Sn3S7·1.25H2O (FJSM-SnS), and systematically studied its Cs+ and Sr2+ ion-exchange performance in different conditions. The structural stabilities and variation, ion-exchange kinetic and isothermal behavior, pH-dependent distribution coeffs. (Kd), ion-exchange in simulated groundwater and ion-exchange applied to chromatog. were studied. The results indicated that the max. Cs+ and Sr2+ ion-exchange capacities of FJSM-SnS were 408.91 and 65.19 mg/g, resp. In particular, FJSM-SnS showed quick ion-exchange ability and wide pH resistance (0.7-12.7) which make it outstanding among the ion-exchangers. An ion-exchange chromatog. column was studied for chalcogenido ion-exchange materials, i.e., a column filled with 3.0 g FJSM-SnS could remove 96-99% of Cs+ and near 100% of Sr2+ at low ionic concns. in 900 bed vols. solns. The title material could be synthesized on a large scale by a facile, 1-pot and economical solvothermal method. The relatively low cost but remarkable ion-exchange performance makes it promising for radionuclide remediation.

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35. 35

    Hunt, J.; Leonard, K.; Hughes, L. Artificial Radionuclides in the Irish Sea from Sellafield: Remobilisation Revisited. J. Radiol. Prot. 2013, 33, 261  DOI: 10.1088/0952-4746/33/2/261

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    Artificial radionuclides in the Irish Sea from Sellafield: remobilization revisited

    Hunt, John; Leonard, Kinson; Hughes, Linda

    Journal of Radiological Protection (2013), 33 (2), 261-279, 19 pp.CODEN: JRPREA; ISSN:1361-6498. (IOP Publishing Ltd.)

    Measured concns. of Cs-137, tritium, Tc-99, Pu-239+240 and Am-241 in representative materials from the Irish Sea were investigated with ref. to continuing remobilization from sediments. Long time series of monitoring data since the 1960s were employed. Cs-137 in sea water and fish shows peaks in concns. normalized to discharge rate (NACs) from 1985 to 1989. This is consistent with the time needed for dispersion in sea water following the preceding redns. in discharges; continuing enhancements of NACs above pre-1970s levels follow, consistent with the effect of activity remobilised from sediment. It is estd. that about 300 TBq of Cs-137 was remobilised from the immediate tidal area around Sellafield from 1989 to 2009. The enhancements in concns. continue to this day, with the effect of remobilization at present being ∼6 TBq y-1, approx. doubling the effect of direct discharges. To provide an indication for the future, the rate of Cs-137 remobilization is decreasing with a half-time of ∼6 years. The data for tritium and Tc-99 were examd. in view of the interest in these radionuclides. The concns. broadly reflect the levels of discharges and the need for dispersion. As expected, there is no evidence of sustained remobilization of tritium, due to its mobility (or low Kd). The same lack of evidence was found to apply for Tc-99 despite known sorption of a small proportion of the discharged activity by Irish Sea sediments. Pu-239+240, by contrast, shows much evidence of the effect of remobilization; concns. in sea water near Sellafield have reduced much more slowly than discharges. At Southerness, ∼50 km away, there was no significant redn. in sea water concns. from 1985 to 1996, and winkles showed an increase then decrease in concns. over this period, consistent with a spreading of activity. This effect was replicated in mud at Garlieston, ∼70 km from Sellafield. For Am-241, the rate of grow-in from Pu-241 has dominated direct discharges since the late 1970s. Grow-in continues today in the Irish Sea at the rate of ∼8 TBq y-1, ∼200 times the rate of direct discharge. Winkles at Southerness show evidence of a spreading effect of Am-241, with an increase then decrease from 1985 to 1996. At Garlieston there was an increase in concns. in mud from 1985 to 1997, and at Carlingford in Northern Ireland the concn. of Am-241 in mud appears to be increasing still. This effect of the spread of activity away from Sellafield may continue, at least in the near future.

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36. 36

    Maloubier, M.; Michel, H.; Solari, P. L.; Moisy, P.; Tribalat, M. A.; Oberhaensli, F. R.; Dechraoui Bottein, M. Y.; Thomas, O. P.; Monfort, M.; Moulin, C.; Den Auwer, C. Speciation of Americium in Seawater and Accumulation in the Marine Sponge Aplysina Cavernicola. Dalton Trans. 2015, 44, 20584– 20596,  DOI: 10.1039/c5dt02805a

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    36

    Speciation of americium in seawater and accumulation in the marine sponge Aplysina cavernicola

    Maloubier, Melody; Michel, Herve; Solari, Pier Lorenzo; Moisy, Philippe; Tribalat, Marie-Aude; Oberhaensli, Francois R.; Dechraoui Bottein, Marie Yasmine; Thomas, Olivier P.; Monfort, Marguerite; Moulin, Christophe; Den Auwer, Christophe

    Dalton Transactions (2015), 44 (47), 20584-20596CODEN: DTARAF; ISSN:1477-9226. (Royal Society of Chemistry)

    The fate of radionuclides in the environment is a cause of great concern for modern society, seen esp. in 2011 after the Fukushima accident. Among the environmental compartments, seawater covers most of the Earth's surface and may be directly or indirectly impacted. The interaction between radionuclides and the marine compartment is therefore essential for better understanding the transfer mechanisms from the hydrosphere to the biosphere. This information allows for the evaluation of the impact on humans via our interaction with the biotope that has been largely undocumented up to now. We attempt to make a link between the speciation of heavy elements in natural seawater and their uptake by a model marine organism. More specifically, because the interaction of actinides with marine invertebrates has been poorly studied, the accumulation in a representative member of the Mediterranean coralligenous habitat, the sponge Aplysina cavernicola, was studied and its uptake curve exposed to a radiotracer 241Am was estd. using a high-purity Ge gamma spectrometer. But in order to go beyond the phenomenol. accumulation rate, the speciation of Am(III) in seawater must be assessed. The speciation of 241Am (and natural Eu as its chem. stable surrogate) in seawater was detd. using a combination of different techniques: time-resolved laser-induced fluorescence (TRLIF), extended x-ray absorption fine structure (EXAFS) at the LIII edge, attenuated total reflectance FTIR (ATR-FTIR) spectroscopy and SEM and the resulting data were compared with the speciation modeling. In seawater, the Am(III) complex (as well as the corresponding Eu complex, although with conformational differences) was identified as a ternary Na biscarbonato complex, whose formula can be tentatively written as NaAm(CO3)2·nH2O. It is therefore this chem. form of Am that is accumulated by the sponge A. cavernicola.

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37. 37

    Chauvin, A.-S.; Bünzli, J.-C. G.; Bochud, F.; Scopelliti, R.; Froidevaux, P. Use of Dipicolinate-Based Complexes for Producing Ion-Imprinted Polystyrene Resins for the Extraction of Yttrium-90 and Heavy Lanthanide Cations. Chem. - Eur. J. 2006, 12, 6852– 6864,  DOI: 10.1002/chem.200501370

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    Use of dipicolinate-based complexes for producing ion-imprinted polystyrene resins for the extraction of yttrium-90 and heavy lanthanide cations

    Chauvin, Anne-Sophie; Bunzli, Jean-Claude G.; Bochud, Francois; Scopelliti, Rosario; Froidevaux, Pascal

    Chemistry - A European Journal (2006), 12 (26), 6852-6864CODEN: CEUJED; ISSN:0947-6539. (Wiley-VCH Verlag GmbH & Co. KGaA)

    Highly selective sepn. of yttrium (and lanthanides) is of interest for the design of radiopharmaceuticals, and an efficient method based on the ion-imprinting concept is proposed here. The synthesis and structural, thermodn. and photophys. characterization of complexes of trivalent yttrium and lanthanides with two new vinyl derivs. of dipicolinic acid, HL1 and L2, are described. The feasibility of using ion-imprinted resins for yttrium and lanthanide sepn. is demonstrated. The resins were obtained by copolymn. with styrene and divinylbenzene and subsequent acid treatment to remove the metal ion. High-resoln. Eu luminescence expts. revealed that the geometry of the complexation sites is well preserved in the imprinted polymers. The ion-imprinted polymer based on HL1 proved to be particularly well adapted for yttrium extn., having a sizeable capacity (8.9 ± 0.2 mg g-1 resin) and a fast rate of extn. (t1/2 = 1.7 min). In addn., lighter and heavier lanthanide ions are sepd. Finally, the resin displays high selectivity for yttrium and lanthanide cations against alkali and alk. earth metals. For instance, in a typical expt., 10 mg of yttrium was extd. from 5 g of milk ash sample by 2 g of the resin. The good sepn. properties displayed by the resin based on HL1 open interesting perspectives for the prodn. of highly pure 90Y and radiolanthanides for medical applications, and for trace anal. of these radio-chems. in food and in the environment.

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    Cejner, M.; Dobrowolski, R. Ion-Imprinted Polymers: Synthesis, Characterization and Applications. Ann. Univ. Mariae Curie-Sklodowska, Sect. AA: Chem. 2016, 70, 67

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    Branger, C.; Meouche, W.; Margaillan, A. Recent Advances on Ion-Imprinted Polymers. React. Funct. Polym. 2013, 73, 859– 875,  DOI: 10.1016/j.reactfunctpolym.2013.03.021

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    Recent advances on ion-imprinted polymers

    Branger, Catherine; Meouche, Walid; Margaillan, Andre

    Reactive & Functional Polymers (2013), 73 (6), 859-875CODEN: RFPOF6; ISSN:1381-5148. (Elsevier Ltd.)

    A review. Selective recognition of metal ions is a real challenge for a large range of applications in the anal. field (from extn. to detection and quantification). For that purpose, ion-imprinted polymers (IIPs) were increasingly developed during the last 15 years on the principle of molecularly imprinted polymers (MIPs). Those imprinted materials are designed to mimic the binding sites of biol. entities and assure an improved recognition of the template species. The aim of this review is to give the current state of the art in the conception of IIPs from the components to the polymn. process. Some applications of those materials will be also discussed.

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    Rao, T. P.; Kala, R.; Daniel, S. Metal Ion-Imprinted Polymers-Novel Materials for Selective Recognition of Inorganics. Anal. Chim. Acta 2006, 578, 105– 116,  DOI: 10.1016/j.aca.2006.06.065

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    Metal ion-imprinted polymers-Novel materials for selective recognition of inorganics

    Rao, T. Prasada; Kala, R.; Daniel, S.

    Analytica Chimica Acta (2006), 578 (2), 105-116CODEN: ACACAM; ISSN:0003-2670. (Elsevier B.V.)

    A review. Ion-imprinted polymers (IIPs) are recently identified nano-porous polymeric materials which on leaching the imprint ion can rebind, sense or transport (when cast as membranes) selectively the target analyte in presence of closely related inorg. ions. The IIPs find interesting applications in solid phase extn., sensors and membrane sepns. of inorgs. Unlike the molecularly imprinted polymers, the IIP field is in its infancy and was briefly reviewed here along with some rough guidelines and concepts for further development of IIPs.

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41. 41

    Saraji, M.; Yousefi, H. Selective Solid-Phase Extraction of Ni(II) by an Ion-Imprinted Polymer from Water Samples. J. Hazard. Mater. 2009, 167, 1152– 1157,  DOI: 10.1016/j.jhazmat.2009.01.111

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    41

    Selective solid-phase extraction of Ni(II) by an ion-imprinted polymer from water samples

    Saraji, Mohammad; Yousefi, Hamideh

    Journal of Hazardous Materials (2009), 167 (1-3), 1152-1157CODEN: JHMAD9; ISSN:0304-3894. (Elsevier B.V.)

    A new ion-imprinted polymer (IIP) material was synthesized by copolymn. of 4-vinylpyridine as monomer, ethyleneglycoldimethacrylate as crosslinking agent and 2,2'-azobis-sobutyronitrile as initiator in the presence of Ni-dithizone complex. The IIP was used as sorbent in a solid-phase extn. column. The effects of sampling vol., elution conditions, sample pH and sample flow rate on the extn. of Ni ions form water samples were studied. The max. adsorption capacity and the relative selectivity coeffs. of imprinted polymer for Ni(II)/Co(II), Ni(II)/Cu(II) and Ni(II)/Cd(II) were calcd. Compared with non-imprinted polymer particles, the IIP had higher selectivity for Ni(II). The relative selectivity factor (α r) values of Ni(II)/Co(II), Ni(II)/Cu(II) and Ni(II)/Cd(II) were 21.6, 54.3, and 22.7, resp., which are greater than 1. The relative std. deviation of the five replicate detns. of Ni(II) was 3.4%. The detection limit for 150 mL of sample was 1.6 μg L-1 using flame at. absorption spectrometry. The developed method was successfully applied to the detn. of trace nickel in water samples with satisfactory results.

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42. 42

    Devi, P.; Barry, S. M.; Houlihan, K. M.; Murphy, M. J.; Turner, P.; Jensen, P.; Rutledge, P. J. Synthesis and Structural Characterisation of Amides from Picolinic Acid and Pyridine-2,6-Dicarboxylic Acid. Sci. Rep. 2015, 5, 9950  DOI: 10.1038/srep09950

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    42

    Synthesis and structural characterisation of amides from picolinic acid and pyridine-2,6-dicarboxylic acid

    Devi, Prarthana; Barry, Sarah M.; Houlihan, Kate M.; Murphy, Michael J.; Turner, Peter; Jensen, Paul; Rutledge, Peter J.

    Scientific Reports (2015), 5 (), 9950pp.CODEN: SRCEC3; ISSN:2045-2322. (Nature Publishing Group)

    Coupling of picolinic acid (pyridine-2-carboxylic acid) and pyridine-2,6-dicarboxylic acid with N-alkylanilines affords a range of mono- and bis-amides in good to moderate yields. These amides are of interest for potential applications in catalysis, coordination chem. and mol. devices. The reaction of picolinic acid with thionyl chloride to generate the acid chloride in situ leads not only to the N-alkyl-N-phenylpicolinamides as expected but also the corresponding 4-chloro-N-alkyl-N-phenylpicolinamides in the one pot. The two products are readily sepd. by column chromatog. Chlorinated products are not obsd. from the corresponding reactions of pyridine-2,6-dicarboxylic acid. X-Ray crystal structures for six of these compds. are described. These structures reveal a general preference for cis amide geometry in which the arom. groups (N-Ph and pyridyl) are cis to each other and the pyridine nitrogen anti to the carbonyl oxygen. Variable temp. 1H NMR expts. provide a window on amide bond isomerisation in soln.

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43. 43

    Kester, D. R.; Duedall, I. W.; Connors, D. N.; Pytkowicz, R. M. Preparation of Artificial Seawater. Limnol. Oceanogr. 1967, 12, 176– 179,  DOI: 10.4319/lo.1967.12.1.0176

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    Preparation of artificial sea water

    Kester, Dana R.; Duedall, Iver W.; Connors, Donald N.; Pytkowicz, Ricardo M.

    Limnology and Oceanography (1967), 12 (1), 176-9CODEN: LIOCAH; ISSN:0024-3590.

    A formulation for prepg. artificial sea water of the same compn. as recently detd. for sea water is presented.

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44. 44

    Bajo, S.; Eikenberg, J. Preparation of a Stable Tracer Solution of Plutonium(IV). Radiochim. Acta 2003, 91, 495– 498,  DOI: 10.1524/ract.91.9.495.19999

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    Preparation of a stable tracer solution of plutonium(IV)

    Bajo, S.; Eikenberg, J.

    Radiochimica Acta (2003), 91 (9), 495-497CODEN: RAACAP; ISSN:0033-8230. (Oldenbourg Wissenschaftsverlag GmbH)

    A method is given for the prepn. of a Pu tracer soln. in 0.10 M NaHSO4 contg. only Pu(IV). This soln. is stable for several years.

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45. 45

    Saito, A.; Roberts, R. A.; Choppin, G. R. Preparation of Solutions of Tracer Level Plutonium(V). Anal. Chem. 1985, 57, 390– 391,  DOI: 10.1021/ac00279a096

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    Preparation of solutions of tracer level plutonium(V)

    Saito, A.; Roberts, R. A.; Choppin, G. R.

    Analytical Chemistry (1985), 57 (1), 390-1CODEN: ANCHAM; ISSN:0003-2700.

    Aq. Pu(V) solns. at tracer concns. initially free from contamination by other oxidn. states of Pu and by redox agents were prepd. by (1) extg. Pu(VI) from an aq. soln. into a soln. of thenoyltrifluoroacetone in cyclohexane; (2) irradiating the sepd. org. phase by fluorescent light, causing redn. of Pu(VI) to Pu(V) and Pu(IV); and (3) stripping Pu(V) into an aq. phase at pH 4-5. The yield of Pu(V) is typically ∼60% of the original amt. of activity.

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46. 46

    Warnken, K. W.; Zhang, H.; Davison, W. Accuracy of the Diffusive Gradients in Thin-Films Technique: Diffusive Boundary Layer and Effective Sampling Area Considerations. Anal. Chem. 2006, 78, 3780– 3787,  DOI: 10.1021/ac060139d

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    46

    Accuracy of the Diffusive Gradients in Thin-Films Technique: Diffusive Boundary Layer and Effective Sampling Area Considerations

    Warnken, Kent W.; Zhang, Hao; Davison, William

    Analytical Chemistry (2006), 78 (11), 3780-3787CODEN: ANCHAM; ISSN:0003-2700. (American Chemical Society)

    When using the diffusive gradients in thin-films (DGT) technique in well-stirred solns., the diffusive boundary layer has generally been ignored on the assumption that it is negligibly thin compared to the total thickness of Δg, i.e., the sum of the thickness of the prefilter and diffusive gel. Deployment of devices with different diffusive layer thicknesses showed that the thickness of the DBL was ∼0.23 mm in moderate to well-stirred solns., but substantially thicker in poorly or unstirred solns. Measurement of the distribution of Cd in the DGT resin gel at high spatial resoln. (100 μm) using laser ablation inductively coupled plasma mass spectrometry showed that the effective sampling window had a larger diam. (2.20 cm) than the geometric diam. of the exposure window (2.00 cm). Lateral diffusion in the gel, which had previously been neglected, therefore increased the effective surface area of the device by ∼20%. The concns. measured by DGT agreed well with the known concns. in std. solns. for all diffusion layer thicknesses, when the effective area and the appropriate diffusive boundary layer (DBL) were used. The extent of the error assocd. with neglecting the DBL and using the geometric window area depends on the gel layer thickness and the true thickness of the DBL, as detd. by the deployment geometry and flow regime. When DGT measurements were made in well-stirred solns. using a 0.80-mm diffusive gel, the effect of neglecting the DBL and using the inappropriate geometric area offset each other, with the error being < ± 10%. For precise measurements, and esp. work involving speciation or kinetic measurements, where DGT devices with different diffusive gel layer thicknesses are deployed, it is necessary to use the effective area and the appropriate DBL thickness in the full DGT equation, which allows for the use of layer-specific diffusion coeffs.

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47. 47

    Garmo, Ø. A.; Røyset, O.; Steinnes, E.; Flaten, T. P. Performance Study of Diffusive Gradients in Thin Films for 55 Elements. Anal. Chem. 2003, 75, 3573– 3580,  DOI: 10.1021/ac026374n

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    47

    Performance Study of Diffusive Gradients in Thin Films for 55 Elements

    Garmo, Oyvind Aaberg; Royset, Oddvar; Steinnes, Eiliv; Flaten, Trond Peder

    Analytical Chemistry (2003), 75 (14), 3573-3580CODEN: ANCHAM; ISSN:0003-2700. (American Chemical Society)

    The technique of diffusive gradients in thin films (DGTs) is a fairly new and useful tool for in situ measurements of labile metal ions in water. The applicability of DGTs was investigated by comparing independently detd. or estd. diffusion coeffs. with DGT effective diffusion coeffs. (DDGT) for 55 elements. The DGTs were exposed at a controlled fluid velocity of 0.1 m/s and a concn. of 1 ng/mL at four pH levels between 4.7 and 6.0, and the DDGT values were detd. from the uptake by the sampler. The measured DDGT values for the elements Co, Ni, Cu, Zn, Cd, Pb, Al, Mn, and Ga were close to previously published values, with some deviations for Pb and Zn. The uptake of V, Cr, Fe, U, Mo, Ti, Ba, and Sr varied with pH, and there were some exptl. problems that require further investigations. A novel set of DDGT values for the lanthanides (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Tb, Yb, Lu, Y) was established. The DDGT values for these were about 10-15% lower than for free ions in water and indicate that diffusion coeffs. of metal ions in the agarose polyacrylamide diffusive hydrogel are 10-15% lower than in water. The high consistency of the data for the lanthanides establishes these elements as new performance test metals for the DGT sampler. The accumulation of the elements Li, Na, K, Rb, Mg, Ca, B, Tl, P, S, As, Bi, Se, Si, Sn, Sb, Te, Zr, Nb, Hf, Ta, W, Th, and Ag was low (DDGT lower than 10% of theor. values). A more efficient elution procedure using concd. nitric acid for the absorbent gel was established, with elution efficiencies between 95% and 100% for most metals. For deployment times of 24 h, detection limits from 0.001 to 1 ng/mL were achieved with moderate precautions to prevent contamination.

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48. 48

    Li, W.; Zhao, J.; Li, C.; Kiser, S.; Jack Cornett, R. Speciation Measurements of Uranium in Alkaline Waters Using Diffusive Gradients in Thin Films Technique. Anal. Chim. Acta 2006, 575, 274– 280,  DOI: 10.1016/j.aca.2006.05.092

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    48

    Speciation measurements of uranium in alkaline waters using diffusive gradients in thin films technique

    Li, Weijia; Zhao, Jiujiang; Li, Chunsheng; Kiser, Stephen; Cornett, R. Jack

    Analytica Chimica Acta (2006), 575 (2), 274-280CODEN: ACACAM; ISSN:0003-2670. (Elsevier B.V.)

    This work studied the application of diffusive gradients in thin films technique (DGT) to U speciation measurements in natural H2O. Two binding phases were examd., a com. available affinity membrane, Whatman DE 81 (DE 81), with amino binding functional groups and the conventionally used Chelex 100 beads imbedded polyacrylamide hydrogel (Chelex) with iminodiacetate functional groups. The DGT devices assembled with the binding phases of DE 81 (DE 81 DGT) and Chelex gel (Chelex DGT) were tested both in synthetic river water solns. and in local river water. DE 81 DGT and Chelex DGT measured 80% and 75% of the total U in synthetic river water soln., resp., and measured 73% and 60% of the total U in St. Lawrence River, Canada, resp. The binding properties of the DE 81 membrane and Chelex gel for U, and the diffusion of uranyl complexes in the polyacrylamide gel (PAM) were also studied.

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49. 49

    Mitchell, P. I.; Vives, J.; Downes, A. B.; Condren, O. M.; León Vintró, L.; Sánchez-Cabeza, J. A. Recent Observations on the Physico-Chemical Speciation of Plutonium in the Irish Sea and the Western Mediterranean. Appl. Radiat. Isot. 1995, 46, 1175– 1190,  DOI: 10.1016/0969-8043(95)00160-F

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    49

    Recent observations on the physicochemical speciation of plutonium in the Irish Sea and the Western Mediterranean

    Mitchell, P. I.; Vives i Batlle, J.; Downes, A. B.; Condren, O. M.; Leon Vintro, L.; Sanchez-Cabeza, J. A.

    Applied Radiation and Isotopes (1995), 46 (11), 1175-90CODEN: ARISEF; ISSN:0969-8043. (Elsevier)

    Data on the physico-chem. speciation of Pu in the Irish Sea and the western Mediterranean, gathered in the course of research expeditions carried out in the period 1988-93, are reviewed in detail in this paper. Measurements of the oxidn. state distribution of 239,240Pu (and 238Pu) in filtered water sampled throughout the Irish Sea show little variation, geog. or temporally, with some 87 ± 6% in the oxidized, Pu(V), state overall. No distinction is obsd. between surface and bottom waters, reflecting both the shallow and the well-mixed nature of these waters. Interestingly, the 241Pu(IV)/239,240Pu(IV) ratio in filtered water from the north-eastern Irish Sea, close to the Sellafield source-term, is significantly higher than the corresponding 241Pu(V)/239,240Pu(V) ratio, while the latter appears to be identical to the 241Pu/239,240Pu ratio in suspended particulate from the same zone. It is suggested that this distinction is of importance in the interpretation of the mechanisms responsible for the hold-up and dispersion of Pu in the near field. The percentage of Pu in colloidal form in open waters, as operationally defined by enhanced sorption on Al2O3, seldom exceeds 15%. There is some evidence of higher percentages in near-shore waters contg. proportionately more Pu in the reduced, Pu(IV), state. Chem. speciation and enhanced sorption analyses on samples of ultrafiltered water confirm that a significant proportion of the Pu(IV) is in a colloidal form and that the size of the colloidal particles or aggregates involved (<10 kD) is considerably smaller than that obsd. in non-saline waters. In contrast to the case of Pu(IV), there is no evidence of significant Pu(V) retention upon ultrafiltration, even by a 1 kD membrane, demonstrating that Pu in an oxidized form is genuinely sol. The oxidn. state distribution of Pu in the western Mediterranean water column was also examd. In open waters, a pronounced sub-surface max. in the Pu(V) concn. is obsd. at depths between 250 m and 500 m. Moreover, the percentage of Pu(IV) is found to increase from 5% at a depth of almost 3000 m to a max. of 70% at about 50 m, most if not all of this increase taking place in the upper half of the water column. Inshore (Gulf of Vera), the percentage of Pu(IV) in surface waters rises to almost 50%, while the percentage in bottom waters remains at 5%. Overall, the bulk of the Pu inventory in the Mediterranean water column is in an oxidized form, particularly in open waters, while the quantities in particulate or colloidal form are comparatively small.

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50. 50

    Kersting, A. B.; Efurd, D. W.; Finnegan, D. L.; Rokop, D. J.; Smith, D. K.; Thompson, J. L. Migration of Plutonium in Ground Water at the Nevada Test Site. Nature 1999, 397, 56– 59,  DOI: 10.1038/16231

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    50

    Migration of plutonium in ground water at the Nevada Test Site

    Kersting, A. B.; Efurd, D. W.; Finnegan, D. L.; Rokop, D. J.; Smith, D. K.; Thompson, J. L.

    Nature (London) (1999), 397 (6714), 56-59CODEN: NATUAS; ISSN:0028-0836. (Macmillan Magazines)

    Mobile colloids (suspended particles in the submicrometer size range) are known to occur naturally in groundwater and have the potential to enhance transport of non-sol. contaminants through sorption. The possible implications of this transport mechanism are of particular concern in the context of radionuclide transport. Significant quantities of the element Pu have been introduced into the environment as a result of nuclear weapons testing and prodn., and nuclear power-plant accidents. Many countries anticipate storing nuclear waste underground. It has been argued that Pu introduced into the subsurface environment is relatively immobile owing to its low soly. in groundwater and strong sorption onto rocks. Nonetheless, colloid-facilitated transport of radionuclides has been implicated in field observations, but unequivocal evidence of subsurface transport is lacking. Moreover, colloid filtration models predict transport over a limited distance resulting in a discrepancy between obsd. and modeled behavior. We report that the radionuclides obsd. in groundwater samples from aquifers at the Nevada Test Site, where hundreds of underground nuclear tests were conducted, are assocd. with the colloidal fraction of the groundwater. The 240Pu/239Pu isotope ratio of the samples establishes that an underground nuclear test 1.3 km north of the sample site is the origin of the Pu. We argue that colloidal groundwater migration must have played an important role in transporting the Pu. Models that either predict limited transport or do not allow for colloid-facilitated transport may thus significantly underestimate the extent of radionuclide migration.

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51. 51

    Novikov, A. P.; Kalmykov, S. N.; Utsunomiya, S.; Ewing, R. C.; Horreard, F.; Merkulov, A.; Clark, S. B.; Tkachev, V. V.; Myasoedov, B. F. Colloid Transport of Plutonium in the Far-Field of the Mayak Production Association, Russia. Science 2006, 314, 638– 641,  DOI: 10.1126/science.1131307

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    51

    Colloid Transport of Plutonium in the Far-Field of the Mayak Production Association, Russia

    Novikov, Alexander P.; Kalmykov, Stepan N.; Utsunomiya, Satoshi; Ewing, Rodney C.; Francois, Horreard; Merkulov, Alex; Clark, Sue B.; Tkachev, Vladimir V.; Myasoedov, Boris F.

    Science (Washington, DC, United States) (2006), 314 (5799), 638-641CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)

    Sorption of actinides, particularly Pu, onto submicrometer-sized colloids increases their mobility; however, these Pu colloids are difficult to detect in the far-field. Actinides on colloids in groundwater from the Mayak Prodn. Assocn., Urals, Russia were identified at the source; Pu activity was ∼1000 becquerels/L. Pu activity was still 0.16 becquerels/L at a distance of 3 km, where 70-90 mol percent of the Pu was sorbed onto colloids, confirming colloids are responsible for long-distance Pu transport. Nano-secondary ion mass spectrometry elemental maps showed that amorphous iron oxide colloids adsorb Pu(IV)hydroxides or carbonates along with uranium carbonates.

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52. 52

    Froidevaux, P.; Steinmann, P.; Pourcelot, L. Long-Term and Long-Range Migration of Radioactive Fallout in a Karst System. Environ. Sci. Technol. 2010, 44, 8479– 8484,  DOI: 10.1021/es100954h

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    52

    Long-Term and Long-Range Migration of Radioactive Fallout in a Karst System

    Froidevaux, Pascal; Steinmann, Philipp; Pourcelot, Laurent

    Environmental Science & Technology (2010), 44 (22), 8479-8484CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)

    Mountainous areas are often covered by little evolved soil from which deposited radionuclides can potentially leak into the vadose zone. In the Swiss Jura Mountains, unusual isotopic ratios from nuclear weapon test (NWT) fallout was obsd., with an apparent loss of NWT Pu relative to Chernobyl origin 137Cs in thinner soil. The karstic watershed of a vauclusian spring was examd. to det. residence times of Pu, 241Am, and 90Sr deposited by global fallout and their resp. mobility in carbonaceous soil. Results showed 90Sr was washed most efficiently from the watershed with a residence time of several hundred years. Estd. Pu residence time was >10 times higher (5000-10,000 years), and 241Am residence time was double that of Pu. Spring water 241Am:239+240Pu isotopic ratios were lower (0.12-0.28) than those of watershed soil (0.382 ± 0.077). Similar differences were obsd. in aquatic moss (241Am:239+240Pu isotopic ratio = 0.05-0.12), which are permanently submerged in spring water. 90Sr was leached from moss with 0.5 M HCl, demonstrating Sr is probably assocd. with CaCO3 pptn. on moss. The higher Pu:Am isotopic ratio obsd. in spring water and moss at the karst outlet showed Pu mobility is enhanced.

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53. 53

    Dumas, T.; Guigue, M.; Moisy, P.; Colina-Ruiz, R.; Mustre de Leon, J.; Matara-Aho, M.; Solari, P. L.; Monfort, M.; Moulin, C.; Beccia, M. R.; Auwer, C. D. Experimental Speciation of Plutonium(IV) in Natural Seawater. ChemistrySelect 2018, 3, 2021– 2024,  DOI: 10.1002/slct.201702762

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    53

    Experimental Speciation of Plutonium(IV) in Natural Seawater

    Dumas, Thomas; Guigue, Mireille; Moisy, Philippe; Colina-Ruiz, Roberto; Mustre de Leon, Jose; Matara-Aho, Minja; Solari, Pier Lorenzo; Monfort, Marguerite; Moulin, Christophe; Beccia, Maria Rosa; Den Auwer, Christophe

    ChemistrySelect (2018), 3 (7), 2021-2024CODEN: CHEMUD; ISSN:2365-6549. (Wiley-VCH Verlag GmbH & Co. KGaA)

    Soly., migration, and bioavailability of plutonium is lacunar because exptl. evidences are missing. We report here on X-ray Absorption Spectroscopy of plutonium in natural seawater. The obsd. valence state is +IV and its speciation corresponds to PuO2 type colloids. Furthermore, aging of the soln. shows a gradient of ordering from hydroxide colloidal species to more cryst. PuO2 colloids.

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