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Updated: Mar 7, 2026
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Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films
Published on: November 9, 2015
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Carbon and Pu isotopes in Baltic Sea sediments
G Lujanienė1, P P Povinec2, H-C Li3
1SRI Center for Physical Sciences and Technology, Vilnius, Lithuania.
Summary
Sediment analysis reveals lower cesium-137 and plutonium-239,240 in the Curonian Lagoon than the Baltic Sea. Carbon isotope ratios (δ13C and Δ14C) also varied between these marine environments.
Area of Science:
- Environmental Science
- Radiochemistry
- Marine Geochemistry
Background:
- Radionuclide distribution in marine sediments is crucial for understanding contaminant transport and fate.
- Cesium-137 (137Cs) and Plutonium isotopes (239,240Pu) are key anthropogenic radionuclides used as tracers.
- Stable carbon isotopes (δ13C) and radiogenic carbon isotopes (Δ14C) provide insights into organic matter sources and degradation processes.
Purpose of the Study:
- To investigate the spatial distribution of 137Cs, 239,240Pu, δ13C, and Δ14C in sediments of the Curonian Lagoon and the open Baltic Sea.
- To compare radionuclide and carbon isotope signatures between the lagoon and the open sea environments.
- To infer the sources and transport pathways of radionuclides and organic matter in the studied areas.
Main Methods:
- Sediment core collection from the Curonian Lagoon and the Baltic Sea.
- Radiochemical analysis for 137Cs and 239,240Pu activity concentrations.
- Stable isotope analysis (δ13C) and radiocarbon analysis (Δ14C) of total organic carbon (TOC).
- Calculation of 240Pu/239Pu atom ratios.
Main Results:
- Lower 137Cs and 239,240Pu activities were observed in the Curonian Lagoon sediments compared to the open Baltic Sea.
- Depleted δ13C values were characteristic of the Curonian Lagoon, while the most depleted Δ14C values were found in the Gotland Deep.
- Global fallout Pu isotopes were dominant in deeper Baltic Sea zones, with higher 240Pu/239Pu atom ratios found in coastal regions.
Conclusions:
- The Curonian Lagoon shows distinct radionuclide and carbon isotope signatures, suggesting different input sources or processes compared to the open Baltic Sea.
- The distribution patterns of 137Cs and 239,240Pu indicate varying degrees of marine influence and sediment dynamics.
- Isotopic data provide valuable information on the provenance and fate of contaminants and organic matter in these interconnected marine systems.
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