Abstract :
Since its discovery half a century ago, plutonium has become the one element which almost everyone has heard about. It is one of the most thoroughly studied, and yet remains one of the most misunderstood. Its environmental occurrence has been pursued with unusual thoroughness and, in common with many other analytical developments, this pursuit has to some extent progressed at a rate dictated by developments in related fields, particularly electronics. But of greater interest is the fact that our considerable yet incomplete knowledge of the distribution of plutonium in the environment has resulted from a unique iterative progression of analytical ingenuity and the need to interpret the behaviour of the element in widely different circumstances. Thus, having overcome the initial difficulties of measuring it at all in some media, and of therefore having to recover it from very large samples in some cases, attention turned to measuring specific isotope ratios and then to discovering the various chemical states of these isotopes. Techniques were developed to analyse plutonium in areas as far apart as hot and cold deserts to the bottom of the oceans. The identification of different chemical forms, their rates of change, and the effect this had on the adsorption of plutonium to different materials, was crucial to the development of predictions of the impacts of plutonium both now and in the future. The techniques which have been developed for this purpose include a wide range of extraction and clean-up procedures, the use of double-isotope tracers, a variety of counting methods plus direct and in situ measurements by contact methods. And yet there is still much to be learned—which will require even more demanding analytical expertise—in order to manage safely the quantities of plutonium which are continuing to arise through the nuclear industries. This paper gives a brief review of the progress to date in the analysis of plutonium in environmental materials.
