Open Access

Uptake and effects of americium-241 on a brackishwater amphipod

  • M. Hoppenheit1,
  • C. N. Murray2 and
  • D. S. Woodhead3
Helgoländer Meeresuntersuchungen33:BF02414742


The present paper reports the results of experimental work undertaken using the brackish-water amphipodGammarus duebeni duebeni and the transuranium nuclide americium-241. Data on the accumulation of this actinide showed that the larger fraction of the total body burden is associated with the exoskeleton. It was found that the body burden remained constant in the range pH 8.0–6.5 even though the water concentrations changed markedly. It would thus appear that the concept of a concentration factor should be re-examined and it is proposed that a factor should be defined in terms of environmental and chemical parameters which represent the bioavailable fraction of the actinide. The effect of americium on survival and moulting was studied at two activity concentrations; the dose rates and absorbed doses under the experimental conditions employed have been estimated. The differences in survival rates between the control and irradiated groups were statistically analyzed and the significant difference at the higher concentration is believed to be due to a synergism between physiological stress and radiotoxicity of americium rather than the chemical toxicity of the element.