Contamination d'organismes marins par le ³H, le ¹³⁴Cs et le ⁶⁰Co

Several marine plants (Acetabularia mediterranea, Dunaliella bioculata, Porphyra sp., Ulva lactuca) and animals (Asteria rubens, Carcinus maenas, Crangon vulgaris and Mytilus edulis) have been used to study the impacts of nuclear releases into the aquatic environment. We have found that ³H, given as tritiated water, is not concentrated by the marine organisms, although a significant amount of radioactivity becomes incorporated in the total organic matter. The uptake of ¹³⁴Cs is rather low, with the exception of the shrimp (C.F. = 20). This fact may be due to the high concentration of K (389 mg/l) in sea water. On the contrary, all the marine organisms tested, were able to concentrate ⁶⁰Co. It it known that the concentration of cobalt in the sea is very low (0.0001 - 0.0005 mg/kg), and that this element is important for the cellular metabolism. The highest accumulation has been observed for the unicellular as well as for the pluricellular marine algae (C.F. = 200-600).