The University of Southampton
University of Southampton Institutional Repository

Time-integrated bioavailability proxy for actinides in a contaminated estuary

Time-integrated bioavailability proxy for actinides in a contaminated estuary
Time-integrated bioavailability proxy for actinides in a contaminated estuary
Actinides accumulate within aquatic biota in concentrations several orders of magnitude higher than in the seawater [the concentration factor (CF)], presenting an elevated radiological and biotoxicological risk to human consumers. CFs currently vary widely for the same radionuclide and species, which limits the accuracy of the modeled radiation dose to the public through seafood consumption. We propose that CFs will show less dispersion if calculated using a time-integrated measure of the labile (bioavailable) fraction instead of a specific spot sample of bulk water. Herein, we assess recently developed configurations of the diffusive gradients in thin films (DGT) sampling technique to provide a more accurate predictor for the bioaccumulation of uranium, plutonium, and americium within the biota of the Sellafield-impacted Esk Estuary (UK). We complement DGT data with the cross-flow ultrafiltration of bulk seawater to assess the DGT-labile fraction versus the bulk concentration. Sequential elution of Fucus vesiculosis reveals preferential internalization and strong intracellular binding of less particle-reactive uranium. We find significant variations between CF values in biota calculated using a spot sample versus using DGT, which suggest an underestimation of the CF by spot sampling in some cases. We therefore recommend a revision of CF values using time-integrated bioavailability proxies.
Americium, Diffusive gradients in thin films / DGT, Plutonium, Sellafield, Uranium, bioaccumulation, concentration factor, radiation dose modeling
2690-0637
Chaplin, Joshua D.
2623b2e6-0c41-4252-ba6c-aa368d72ad28
Christl, Marcus
987c42b7-0376-40e0-a23d-7f74cd151c88
Cundy, Andy
994fdc96-2dce-40f4-b74b-dc638286eb08
Warwick, Phillip
f2675d83-eee2-40c5-b53d-fbe437f401ef
Gaca, Pawel
3d23473d-db81-436a-a12d-ad707db4abc8
Bochud, François
eaec472c-9935-4338-a3c1-aba4038776e4
Froidevaux, Pascal
0de4e2c6-9158-43dc-9f6e-66dbf27e6641
Chaplin, Joshua D.
2623b2e6-0c41-4252-ba6c-aa368d72ad28
Christl, Marcus
987c42b7-0376-40e0-a23d-7f74cd151c88
Cundy, Andy
994fdc96-2dce-40f4-b74b-dc638286eb08
Warwick, Phillip
f2675d83-eee2-40c5-b53d-fbe437f401ef
Gaca, Pawel
3d23473d-db81-436a-a12d-ad707db4abc8
Bochud, François
eaec472c-9935-4338-a3c1-aba4038776e4
Froidevaux, Pascal
0de4e2c6-9158-43dc-9f6e-66dbf27e6641

Chaplin, Joshua D., Christl, Marcus, Cundy, Andy, Warwick, Phillip, Gaca, Pawel, Bochud, François and Froidevaux, Pascal (2022) Time-integrated bioavailability proxy for actinides in a contaminated estuary. ACS EST Water. (doi:10.1021/acsestwater.2c00194).

Record type: Article

Abstract

Actinides accumulate within aquatic biota in concentrations several orders of magnitude higher than in the seawater [the concentration factor (CF)], presenting an elevated radiological and biotoxicological risk to human consumers. CFs currently vary widely for the same radionuclide and species, which limits the accuracy of the modeled radiation dose to the public through seafood consumption. We propose that CFs will show less dispersion if calculated using a time-integrated measure of the labile (bioavailable) fraction instead of a specific spot sample of bulk water. Herein, we assess recently developed configurations of the diffusive gradients in thin films (DGT) sampling technique to provide a more accurate predictor for the bioaccumulation of uranium, plutonium, and americium within the biota of the Sellafield-impacted Esk Estuary (UK). We complement DGT data with the cross-flow ultrafiltration of bulk seawater to assess the DGT-labile fraction versus the bulk concentration. Sequential elution of Fucus vesiculosis reveals preferential internalization and strong intracellular binding of less particle-reactive uranium. We find significant variations between CF values in biota calculated using a spot sample versus using DGT, which suggest an underestimation of the CF by spot sampling in some cases. We therefore recommend a revision of CF values using time-integrated bioavailability proxies.

Text
acsestwater.2c00194 - Version of Record
Download (4MB)

More information

Accepted/In Press date: 5 August 2022
e-pub ahead of print date: 1 September 2022
Additional Information: Funding Information: We gratefully acknowledge funding under the Swiss National Science Foundation grant no 175492, which supported the PhD studentship associated with this project and the open access publishing of this work. We are also grateful to Jamie, Sam, and Tamsin Cundy for their contributions to the on-site fieldwork and to David Reading for additional laboratory assistance. Publisher Copyright: ©
Keywords: Americium, Diffusive gradients in thin films / DGT, Plutonium, Sellafield, Uranium, bioaccumulation, concentration factor, radiation dose modeling

Identifiers

Local EPrints ID: 470479
URI: http://eprints.soton.ac.uk/id/eprint/470479
ISSN: 2690-0637
PURE UUID: 89c3333c-bb21-4ee7-b518-5ca73714fce0
ORCID for Andy Cundy: ORCID iD orcid.org/0000-0003-4368-2569
ORCID for Phillip Warwick: ORCID iD orcid.org/0000-0001-8774-5125

Catalogue record

Date deposited: 11 Oct 2022 16:45
Last modified: 13 Oct 2022 01:34

Export record

Altmetrics

Contributors

Author: Joshua D. Chaplin
Author: Marcus Christl
Author: Andy Cundy ORCID iD
Author: Phillip Warwick ORCID iD
Author: Pawel Gaca
Author: François Bochud
Author: Pascal Froidevaux

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×