INFLUENCE OF TEMPERATURE ON THE ACCUMULATION AND RETENTION OF 11 RADIONUCLIDES BY THE MARINE ALGA FUCUS-VESICULOSUS (L.)

Accumulation of the radionuclides Am-241, Ag-110m, Ba-133, Cd-109, Co- 57-cobalamine, Co-60, Cs-134, Eu-152, Mn-54, Ru-106 and Zn-65 in the b rown macroalga Fucus vesiculosus (L.) Phaeophyceae, was compared at 2 degrees C and 12 degrees C in a series of laboratory radiotracer exper iments. Concentration factors in the thallus were temperature-dependen t and significantly decreased at 2 degrees C for Ag-110m, Cd-109, Co-6 0, Mn-54 and Zn-65 (CF=439, 51, 101, 92 and 162, respectively) but not for Am-241, Ba-133, Cs-134, Eu-152 and organic Co-57 (CF=329, 210, 3. 3, 470 and 214, respectively); hence, for these last isotopes concentr ation factors in this species derived from temperate latitude (12 degr ees C) studies can probably be applied to radiological assessments mad e under Arctic conditions, Between 2 and 14 days of depuration, the ra dionuclides, except Ba-133 and Cs-134, remained tightly bound to the a lga. Our results suggest that: 1, temperature must be considered when modelling the radiological impact of radioactive waste dumping in the Arctic Seas; and 2, Fucus spp, would be excellent bioindicators of rad ionuclide contamination and dispersion in the Barents and Kara Seas. ( C) 1997 Elsevier Science Ltd, All rights reserved.