Radiocaesium from Chernobyl in Swedish moose

Area of Science:

• Environmental Science
• Radiological Science
• Wildlife Ecology

Background:

• The Chernobyl disaster in 1986 led to widespread radioactive contamination.
• Cesium-137 ((137)Cs) is a significant radionuclide released, known for its long half-life and uptake by biological tissues.
• Moose are large herbivores whose muscle tissue can accumulate environmental contaminants.

Purpose of the Study:

• To determine the (137)Cs activity concentrations in moose muscle samples from central Sweden.
• To investigate the relationship between (137)Cs levels in moose and environmental factors, including ground deposition and habitat characteristics.

Main Methods:

• Analysis of (137)Cs activity concentrations in moose muscle samples collected pre- and post-Chernobyl.
• Comparison of (137)Cs levels across different muscle types (neck, thigh, leg).
• Statistical correlation analysis between (137)Cs concentrations, ground deposition levels, and the percentage of farmland within moose home ranges.

Main Results:

• Pre-Chernobyl moose muscle had a mean (137)Cs concentration of 23 Bq kg(-1).
• Post-Chernobyl (1986-1987), mean (137)Cs concentrations in moose muscle increased significantly to 760 Bq kg(-1) and 664 Bq kg(-1), respectively.
• A significant positive correlation was found between ground deposition of (137)Cs and muscle activity concentration.
• Moose inhabiting home ranges with a lower percentage of farmland exhibited higher (137)Cs activity concentrations.

Conclusions:

• Moose muscle (137)Cs activity concentrations in central Sweden were markedly elevated following the Chernobyl accident.
• Ground deposition of (137)Cs is a key factor, but habitat characteristics, specifically farmland percentage, also play a crucial role in modulating radionuclide uptake in moose.
• These findings highlight the complex interplay between environmental contamination, habitat use, and wildlife exposure to radionuclides.