Publication Abstract

The uptake of radioactive phosphorus by brown trout from water and food

K. Winpenny, J.F. Knowles and D.L. Smith

Brown trout were exposed to ³²P in their water tank (7.4 Bq l^-1) and the uptake to muscle followed over 6 weeks. A steady state concentration factor (C_ss) of 1.7 and a biological half-time for clearance (t_b½) of 45 days were calculated from the results. The low C_SS indicates that uptake from water is not a major route of ³²P accumulation in these fish. Brown trout were given a single ³²P-spiked meal and the uptake and clearance in muscle, liver and blood followed over 6 weeks. Assimilation of the isotope by these organs was low, the maximum activity in the whole muscle reaching only 0.2-0.4% of that in the meal with lower values in the other two or gans. There was no appreciable clearance of ³²P from muscle during the experiment. The slow clearance of ³²P after uptake from water and lack of any clearance after uptake from food indicates that the C_SS for this isotope following uptake by either route is likely to depend on radioactive decay rather than physiological clearance.

Reference:

K. Winpenny, J.F. Knowles and D.L. Smith, 1996. The uptake of radioactive phosphorus by brown trout from water and food. Journal of Environmental Radioactivity, 38: 211-221