Radioactivity in sea water

Seawater is sampled from a number of localities  around Zealand. Due to the comparatively high deposition of 137Cs from the Chernobyl accident, the surface water concentrations of this radionuclide remained elevated for considerable time. The main source of 137Cs in Danish seas after the Chernobyl accident has been the Baltic sea. 99Tc concentrations originate to a great extent from discharges from the nuclear fuel reprocessing plants in Sellafield, UK, and Cap de la Hague, France.  90Sr and 99Tc concentrations are measured by beta counting, after sample volume reduction and removal of all other beta emitters, since beta counting is not radionuclide-specific. 137Cs is more conveniently measured in a gamma spectrometer, following volume reduction.

Caesium-137 in seawater around Zealand, 1972-2009
Strontium-90 in seawater around Zealand, 1962-2009
Technetium-99 in seawater around Zealand, 1999-2009

Page updated  by   25.08.2009


Kasper Grann Andersson
Senior Scientist
Radiation Research (NUK)
Dir tel+45 46774173