Radioactive contamination of filamentous green algae in the Hungarian reach of the river Danube

In accordance with the Hungarian nuclear power program, river water monitoring techniques should be developed. From among algae of various species of river Danube the localized and well-propagating filamentous green algae (Cladophora sp.; Vaucheria sp.) were investigated. The activity concentration of gamma-radiating nuclides absorbed by algae was determined with a Canberra 8100 type Ge(Li)-spectrometer. This apparatus facilitated radioactivity measurements on wet samples or samples subjected to simple physical preparation. The metabolic character and accumulative abilities of filamentous green algae showed that they are suitable indicators of radionuclide contamination of the water ecosystem. 131I nuclide at min. 72.5 mBq/g to max. 5440.0 mBq/g, and other fission products from 55 mBq/g to 929 mBq/g were observed. (author)