ACCUMULATION FROM WATER AND DEPURATION OF AG-110M BY A FRESH-WATER FISH, SALMO-TRUTTA L

The accumulation kinetics were followed on a group of 20 individuals maintained in spring water contaminated with 30 Bq ml-1 of 110mAg. Because of a very significant radionuclide adsorption on all available surfaces, and in order to allow investigation into uptake under chronic exposure, the contaminated water was completely renewed three times a week. The evolution of the radionuclide concentration in the trout followed slow uptake kinetics with a maximum contamination level reached after a very long period of ca 900 days of exposure. The concentration factor, calculated from the ratio of the integrals of the curves representing the radionuclide concentration variations in the unfiltered water and in the fish, reached a maximum value of 9 (w/w). At the end of the exposure phase, the 110mAg organotropism, investigated on 10 individuals, showed a very high concentration in the liver which accounted for 70% of the total radioactivity in the fish. Immediately following the accumulation period (57 days), the remaining specimens were placed in non-radioactive water. After 28 days, their radioactivity level and the 110mAg distribution in the tissues were the same as at the end of the uptake phase. © 1990.