Strontium-90 in the Australian Environment, 1957–58

Abstract

Within the sampling errors, and apart frnm some local variations noted, the levels of strontium-90 in the material examined are uniform throughout Australia. This indicates that the strontium-90 fall-out over the continent arises from high-yield fission weapon tests overseas: as expected the contribution from local weapon tests is too small to be detected. The rate of deposition of strontium90 and its accumulation in Australian soils are one-fourth to one-third those in the more densely populated areas of the northern hemisphere. The levels of strontium-90 in Australian human bone tissue and milk lie between onethird and one-half those in the northern hemisphere. This level is a little higher than would be expected from the fall-out rate and the soil data. but the differenrs is not established statistically. If further experiments prove this difference to be real it would be hard to explain satisfactorily. The possible biological consequences to the population of Australia, of the fall-out levels reported in this paper, have been assessed by the Australian National Radiation Advisory Committee. The Committee concluded that the possible hazards are very small in comparison with those already accepted in technically advanced communities. (auth)