PLUTONIUM IN THE MARINE ENVIRONMENT

SUMMARY

The shipping of plutonium from Europe to Japan around the Cape is a contentious issue which has raised public concern that South Africans may be at risk to plutonium exposure should an accident occur: The paper describes the containers in which the plutonium (in the form of plutonium oxide, PuO₂) is housed and consequences of the unlikely event of these becoming ruptured. Wind-born pollution is considered not to be a likely scenario, with the PuO₂ particles more likely to remain practically insoluble and sedimenting. Plutonium aqueous and environmental chemistry is briefly discussed. Some computer modelling whereby PuO₂ is brought into contact with seawater has been performed and the results are presented. The impact on marine organisms is discussed in terms of studies performed at marine dump sites and after the crash of a bomber carrying nuclear warheads at Thule, Greenland in 1968. Various pathways from the sea to land are considered in the light of studies done at Sellafield, a reprocessing plant in the United Kingdom. Some recent debates, such as that on the leukaemia cluster at Sellafield, in the popular scientific press are described. Plutonium biochemistry and toxicity are discussed as well as medical histories of workers exposed to plutonium.