Unravelling 5 decades of anthropogenic 236U discharge from nuclear reprocessing plants ...

• Main Authors: Castrillejo, Maxi, Witbaard, Rob, Casacuberta, Núria, Richardson, Christopher A., Dekker, Rob, Synal, Hans-Arno, Christl, Marcus
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2020
• Subjects: Radioactive contamination; Uranium-236; Ocean circulation; Sclerochronology; Cerastoderma edule; Arctic; Arctic Ocean
• Online Access: https://dx.doi.org/10.3929/ethz-b-000399761; http://hdl.handle.net/20.500.11850/399761

Marine biogenic materials such as corals, shells, or seaweed have long been recognized as recorders of environmental conditions. Here, the bivalve Cerastoderma edule is used for the first time as a recorder of past seawater contamination with anthropogenic uranium, specifically 236U. Several studies have employed the authorized radioactive releases, including 236U, from nuclear reprocessing plants in La Hague, France, into the English Channel, and Sellafield, England, into the Irish Sea, to trace Atlantic waters and to understand recent climate induced circulation changes in the Arctic Ocean. Anthropogenic 236U has emerged over recent years as a new transient tracer to track these changes, but its application has been challenged owing to paucity of fundamental data on the input (timing and amount) of 236U from Sellafield. Here, we present 236U/238U data from bivalve shells collected close to La Hague and Sellafield from two unique shell collections that allow the reconstruction of the historical 236U ... : Science of The Total Environment, 717 ...