Plutonium redistribution by biological activity in Irish Sea sediments

Area of Science:

• Marine Biology
• Environmental Science
• Radiochemistry

Background:

• Transuranium nuclides, including plutonium, are discharged into coastal waters.
• Understanding the environmental fate of these radionuclides is crucial for risk assessment.
• Benthic ecosystems play a role in sediment and contaminant dynamics.

Purpose of the Study:

• To investigate the influence of benthic fauna on plutonium redistribution in Irish Sea sediments.
• To quantify the role of Maxmulleria lankesteri in the vertical transport of plutonium.

Main Methods:

• Analysis of plutonium concentrations in sediment and burrow linings.
• Studying the burrowing behavior of the echiuroid Maxmulleria lankesteri.
• Sediment core sampling and radiometric analysis.

Main Results:

• Maxmulleria lankesteri burrows extend to depths greater than 40 cm.
• Analysis of burrow linings indicates plutonium accumulation.
• The burrowing activity of this species facilitates plutonium removal to deeper sediment layers.

Conclusions:

• The echiuroid Maxmulleria lankesteri significantly influences plutonium redistribution in marine sediments.
• This bioturbation process enhances the sequestration of plutonium into deeper seabed environments.
• Findings are important for modeling the long-term fate of plutonium in coastal ecosystems.